<?xml version="1.0" encoding="US-ASCII"?>
<!--XBRL Document Created with Wdesk from Workiva, formerly WebFilings-->
<!-- -->
<linkbase xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns="http://www.xbrl.org/2003/linkbase" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <roleRef roleURI="http://www.afginc.com/role/AccountingPolicies" xlink:href="afg-20140930.xsd#AccountingPolicies" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/AccountingPoliciesDetails" xlink:href="afg-20140930.xsd#AccountingPoliciesDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/AccountingPoliciesPolicies" xlink:href="afg-20140930.xsd#AccountingPoliciesPolicies" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/Acquisitions" xlink:href="afg-20140930.xsd#Acquisitions" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/AcquisitionsDetails" xlink:href="afg-20140930.xsd#AcquisitionsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/AcquisitionsDetailsTextual" xlink:href="afg-20140930.xsd#AcquisitionsDetailsTextual" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/AcquisitionsTables" xlink:href="afg-20140930.xsd#AcquisitionsTables" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ConsolidatedBalanceSheetUnaudited" xlink:href="afg-20140930.xsd#ConsolidatedBalanceSheetUnaudited" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ConsolidatedBalanceSheetUnauditedParenthetical" xlink:href="afg-20140930.xsd#ConsolidatedBalanceSheetUnauditedParenthetical" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ConsolidatedStatementOfCashFlowsUnaudited" xlink:href="afg-20140930.xsd#ConsolidatedStatementOfCashFlowsUnaudited" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ConsolidatedStatementOfChangesInEquityUnaudited" xlink:href="afg-20140930.xsd#ConsolidatedStatementOfChangesInEquityUnaudited" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ConsolidatedStatementOfComprehensiveIncomeUnaudited" xlink:href="afg-20140930.xsd#ConsolidatedStatementOfComprehensiveIncomeUnaudited" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ConsolidatedStatementOfEarningsUnaudited" xlink:href="afg-20140930.xsd#ConsolidatedStatementOfEarningsUnaudited" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/Contingencies" xlink:href="afg-20140930.xsd#Contingencies" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ContingenciesDetails" xlink:href="afg-20140930.xsd#ContingenciesDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/DeferredPolicyAcquisitionCosts" xlink:href="afg-20140930.xsd#DeferredPolicyAcquisitionCosts" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/DeferredPolicyAcquisitionCostsDetails" xlink:href="afg-20140930.xsd#DeferredPolicyAcquisitionCostsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/DeferredPolicyAcquisitionCostsDetailsTextual" xlink:href="afg-20140930.xsd#DeferredPolicyAcquisitionCostsDetailsTextual" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/DeferredPolicyAcquisitionCostsTables" xlink:href="afg-20140930.xsd#DeferredPolicyAcquisitionCostsTables" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/Derivatives" xlink:href="afg-20140930.xsd#Derivatives" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/DerivativesDetails" xlink:href="afg-20140930.xsd#DerivativesDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/DerivativesDetails1" xlink:href="afg-20140930.xsd#DerivativesDetails1" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/DerivativesDetailsTextual" xlink:href="afg-20140930.xsd#DerivativesDetailsTextual" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/DerivativesTables" xlink:href="afg-20140930.xsd#DerivativesTables" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/DocumentAndEntityInformation" xlink:href="afg-20140930.xsd#DocumentAndEntityInformation" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/FairValueMeasurements" xlink:href="afg-20140930.xsd#FairValueMeasurements" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/FairValueMeasurementsDetails" xlink:href="afg-20140930.xsd#FairValueMeasurementsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/FairValueMeasurementsDetails1" xlink:href="afg-20140930.xsd#FairValueMeasurementsDetails1" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/FairValueMeasurementsDetails2" xlink:href="afg-20140930.xsd#FairValueMeasurementsDetails2" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/FairValueMeasurementsDetails3" xlink:href="afg-20140930.xsd#FairValueMeasurementsDetails3" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/FairValueMeasurementsDetails4" xlink:href="afg-20140930.xsd#FairValueMeasurementsDetails4" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/FairValueMeasurementsDetailsTextual" xlink:href="afg-20140930.xsd#FairValueMeasurementsDetailsTextual" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/FairValueMeasurementsTables" xlink:href="afg-20140930.xsd#FairValueMeasurementsTables" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/GoodwillAndOtherIntangibles" xlink:href="afg-20140930.xsd#GoodwillAndOtherIntangibles" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/GoodwillAndOtherIntangiblesDetailsTextual" xlink:href="afg-20140930.xsd#GoodwillAndOtherIntangiblesDetailsTextual" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/IncomeTaxes" xlink:href="afg-20140930.xsd#IncomeTaxes" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/IncomeTaxesDetails" xlink:href="afg-20140930.xsd#IncomeTaxesDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/IncomeTaxesDetailsTextual" xlink:href="afg-20140930.xsd#IncomeTaxesDetailsTextual" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/IncomeTaxesTables" xlink:href="afg-20140930.xsd#IncomeTaxesTables" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/Investments" xlink:href="afg-20140930.xsd#Investments" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/InvestmentsDetails" xlink:href="afg-20140930.xsd#InvestmentsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/InvestmentsDetails1" xlink:href="afg-20140930.xsd#InvestmentsDetails1" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/InvestmentsDetails2" xlink:href="afg-20140930.xsd#InvestmentsDetails2" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/InvestmentsDetails3" xlink:href="afg-20140930.xsd#InvestmentsDetails3" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/InvestmentsDetails4" xlink:href="afg-20140930.xsd#InvestmentsDetails4" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/InvestmentsDetails5" xlink:href="afg-20140930.xsd#InvestmentsDetails5" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/InvestmentsDetails6" xlink:href="afg-20140930.xsd#InvestmentsDetails6" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/InvestmentsDetails7" xlink:href="afg-20140930.xsd#InvestmentsDetails7" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/InvestmentsDetailsTextual" xlink:href="afg-20140930.xsd#InvestmentsDetailsTextual" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/InvestmentsTables" xlink:href="afg-20140930.xsd#InvestmentsTables" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/LongTermDebt" xlink:href="afg-20140930.xsd#LongTermDebt" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/LongTermDebtDetails" xlink:href="afg-20140930.xsd#LongTermDebtDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/LongTermDebtDetails1" xlink:href="afg-20140930.xsd#LongTermDebtDetails1" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/LongTermDebtDetailsTextual" xlink:href="afg-20140930.xsd#LongTermDebtDetailsTextual" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/LongTermDebtTables" xlink:href="afg-20140930.xsd#LongTermDebtTables" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ManagedInvestmentEntities" xlink:href="afg-20140930.xsd#ManagedInvestmentEntities" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ManagedInvestmentEntitiesDetails" xlink:href="afg-20140930.xsd#ManagedInvestmentEntitiesDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ManagedInvestmentEntitiesDetailsTextual" xlink:href="afg-20140930.xsd#ManagedInvestmentEntitiesDetailsTextual" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ManagedInvestmentEntitiesTables" xlink:href="afg-20140930.xsd#ManagedInvestmentEntitiesTables" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/SegmentsOfOperations" xlink:href="afg-20140930.xsd#SegmentsOfOperations" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/SegmentsOfOperationsDetails" xlink:href="afg-20140930.xsd#SegmentsOfOperationsDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/SegmentsOfOperationsDetails1" xlink:href="afg-20140930.xsd#SegmentsOfOperationsDetails1" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/SegmentsOfOperationsDetailsTextual" xlink:href="afg-20140930.xsd#SegmentsOfOperationsDetailsTextual" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/SegmentsOfOperationsTables" xlink:href="afg-20140930.xsd#SegmentsOfOperationsTables" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ShareholdersEquity" xlink:href="afg-20140930.xsd#ShareholdersEquity" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ShareholdersEquityDetails" xlink:href="afg-20140930.xsd#ShareholdersEquityDetails" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ShareholdersEquityDetails1" xlink:href="afg-20140930.xsd#ShareholdersEquityDetails1" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ShareholdersEquityDetails2" xlink:href="afg-20140930.xsd#ShareholdersEquityDetails2" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ShareholdersEquityDetailsTextual" xlink:href="afg-20140930.xsd#ShareholdersEquityDetailsTextual" xlink:type="simple" />
  <roleRef roleURI="http://www.afginc.com/role/ShareholdersEquityTables" xlink:href="afg-20140930.xsd#ShareholdersEquityTables" xlink:type="simple" />
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" xlink:type="simple" />
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" xlink:type="simple" />
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" xlink:type="simple" />
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" xlink:type="simple" />
  <arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" xlink:type="simple" />
  <definitionLink xlink:role="http://www.afginc.com/role/AccountingPolicies" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/AccountingPoliciesDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_VariableInterestEntityLineItems" xlink:label="loc_us-gaap_VariableInterestEntityLineItems_F481EEAC9D7263BC003622114EBB8AD2" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfVariableInterestEntitiesTable" xlink:label="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_71A32EB9918264FA87FD22114EBA89F6" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_F481EEAC9D7263BC003622114EBB8AD2" xlink:to="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_71A32EB9918264FA87FD22114EBA89F6" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis" xlink:label="loc_us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis_AD00FCEA296B5441964222114EBAD00B" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_71A32EB9918264FA87FD22114EBA89F6" xlink:to="loc_us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis_AD00FCEA296B5441964222114EBAD00B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassificationOfVariableInterestEntityDomain" xlink:label="loc_us-gaap_ClassificationOfVariableInterestEntityDomain_E9AA29AFB8502043BFA322114EBA4F65_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis_AD00FCEA296B5441964222114EBAD00B" xlink:to="loc_us-gaap_ClassificationOfVariableInterestEntityDomain_E9AA29AFB8502043BFA322114EBA4F65_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassificationOfVariableInterestEntityDomain" xlink:label="loc_us-gaap_ClassificationOfVariableInterestEntityDomain_E9AA29AFB8502043BFA322114EBA4F65" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis_AD00FCEA296B5441964222114EBAD00B" xlink:to="loc_us-gaap_ClassificationOfVariableInterestEntityDomain_E9AA29AFB8502043BFA322114EBA4F65" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_NewCollateralizedLoanObligationTemporaryWarehousingEntitiesMember" xlink:label="loc_afg_NewCollateralizedLoanObligationTemporaryWarehousingEntitiesMember_02F9F2161CEAEC680CA122114EBA8E75" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassificationOfVariableInterestEntityDomain_E9AA29AFB8502043BFA322114EBA4F65" xlink:to="loc_afg_NewCollateralizedLoanObligationTemporaryWarehousingEntitiesMember_02F9F2161CEAEC680CA122114EBA8E75" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_VariableInterestEntityConsolidatedCarryingAmountAssets" xlink:label="loc_us-gaap_VariableInterestEntityConsolidatedCarryingAmountAssets_80BD0601B668FC3954B522114EBB8146" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_F481EEAC9D7263BC003622114EBB8AD2" xlink:to="loc_us-gaap_VariableInterestEntityConsolidatedCarryingAmountAssets_80BD0601B668FC3954B522114EBB8146" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_VariableInterestEntityConsolidatedCarryingAmountLiabilities" xlink:label="loc_us-gaap_VariableInterestEntityConsolidatedCarryingAmountLiabilities_6F2BF781213974320A9A22114EBB581D" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_F481EEAC9D7263BC003622114EBB8AD2" xlink:to="loc_us-gaap_VariableInterestEntityConsolidatedCarryingAmountLiabilities_6F2BF781213974320A9A22114EBB581D" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_60EEB29027762343B1AC22114EBBF1C2" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_F481EEAC9D7263BC003622114EBB8AD2" xlink:to="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_60EEB29027762343B1AC22114EBBF1C2" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_D1406DA7FE9DEE7C81AD22114EBB95CD" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_F481EEAC9D7263BC003622114EBB8AD2" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_D1406DA7FE9DEE7C81AD22114EBB95CD" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_MaturityPeriodOfShortTermInvestmentMaximum" xlink:label="loc_afg_MaturityPeriodOfShortTermInvestmentMaximum_BDC292DA6012BFFF32C622114EBB75DD" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_F481EEAC9D7263BC003622114EBB8AD2" xlink:to="loc_afg_MaturityPeriodOfShortTermInvestmentMaximum_BDC292DA6012BFFF32C622114EBB75DD" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/AccountingPoliciesPolicies" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/Acquisitions" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/AcquisitionsDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_C1167AE0833BC902758E22114E911A72" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_A39ED06B1695E2FA73A322114E91AE74" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_C1167AE0833BC902758E22114E911A72" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_A39ED06B1695E2FA73A322114E91AE74" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_7D0BA88C0340AAD67D4622114E910C38" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_A39ED06B1695E2FA73A322114E91AE74" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_7D0BA88C0340AAD67D4622114E910C38" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_CAD35F91314E7D6491EC22114E91578C_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_7D0BA88C0340AAD67D4622114E910C38" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_CAD35F91314E7D6491EC22114E91578C_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_CAD35F91314E7D6491EC22114E91578C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_7D0BA88C0340AAD67D4622114E910C38" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_CAD35F91314E7D6491EC22114E91578C" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SummitHoldingSoutheastIncMember" xlink:label="loc_afg_SummitHoldingSoutheastIncMember_B54D08DF2D75E530CB5622114E91C479" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_CAD35F91314E7D6491EC22114E91578C" xlink:to="loc_afg_SummitHoldingSoutheastIncMember_B54D08DF2D75E530CB5622114E91C479" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PaymentsToAcquireBusinessesGross" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesGross_A8B11D3751013597441322114E916943" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_C1167AE0833BC902758E22114E911A72" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesGross_A8B11D3751013597441322114E916943" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_8E5E072A4A7DF15891FB22114E911FAF" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_C1167AE0833BC902758E22114E911A72" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_8E5E072A4A7DF15891FB22114E911FAF" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_B81814F3500BEE2D389322114E923E96" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_8E5E072A4A7DF15891FB22114E911FAF" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_B81814F3500BEE2D389322114E923E96" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedFixedMaturitiesAvailableforSale" xlink:label="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedFixedMaturitiesAvailableforSale_C55428C014516AB65CCB22114E9211EA" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_8E5E072A4A7DF15891FB22114E911FAF" xlink:to="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedFixedMaturitiesAvailableforSale_C55428C014516AB65CCB22114E9211EA" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedReinsuranceRecoverables" xlink:label="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedReinsuranceRecoverables_D5C686A3AD07D1FFBAF122114E924C66" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_8E5E072A4A7DF15891FB22114E911FAF" xlink:to="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedReinsuranceRecoverables_D5C686A3AD07D1FFBAF122114E924C66" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedPremiumsReceivableNet" xlink:label="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedPremiumsReceivableNet_BD7B2A0B83A48CD3B45B22114E9230B3" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_8E5E072A4A7DF15891FB22114E911FAF" xlink:to="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedPremiumsReceivableNet_BD7B2A0B83A48CD3B45B22114E9230B3" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssetsNoncurrent" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssetsNoncurrent_B09812E0787D8DEB5AA822114E928B04" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_8E5E072A4A7DF15891FB22114E911FAF" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxAssetsNoncurrent_B09812E0787D8DEB5AA822114E928B04" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_FD3FCAE76168AD00090422114E929370" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_8E5E072A4A7DF15891FB22114E911FAF" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_FD3FCAE76168AD00090422114E929370" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets_A5FFED0618ABBDF5403D22114E92E8BB" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_8E5E072A4A7DF15891FB22114E911FAF" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets_A5FFED0618ABBDF5403D22114E92E8BB" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_789FA19750B0B22AD2C622114E922A97" xlink:type="locator" />
    <definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_8E5E072A4A7DF15891FB22114E911FAF" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_789FA19750B0B22AD2C622114E922A97" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_A01B136655D7C85AE56022114E92AE90" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_C1167AE0833BC902758E22114E911A72" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_A01B136655D7C85AE56022114E92AE90" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedLiabilityforClaimsandClaimsAdjustmentExpensePropertyCasualtyLiability" xlink:label="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedLiabilityforClaimsandClaimsAdjustmentExpensePropertyCasualtyLiability_7C29FA619BE06A3335CC22114E929219" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_A01B136655D7C85AE56022114E92AE90" xlink:to="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedLiabilityforClaimsandClaimsAdjustmentExpensePropertyCasualtyLiability_7C29FA619BE06A3335CC22114E929219" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedUnearnedPremiums" xlink:label="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedUnearnedPremiums_9DD0EA130C9D9D7AD95222114E92C349" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_A01B136655D7C85AE56022114E92AE90" xlink:to="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedUnearnedPremiums_9DD0EA130C9D9D7AD95222114E92C349" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedReinsurancePayable" xlink:label="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedReinsurancePayable_CF9FC11AA150E51668D622114E92F569" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_A01B136655D7C85AE56022114E92AE90" xlink:to="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedReinsurancePayable_CF9FC11AA150E51668D622114E92F569" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther_D6BA0887A18ABB4283B722114E92F137" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_A01B136655D7C85AE56022114E92AE90" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther_D6BA0887A18ABB4283B722114E92F137" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_CBF5716024A8F69E5F0722114E9371F0" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_A01B136655D7C85AE56022114E92AE90" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_CBF5716024A8F69E5F0722114E9371F0" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_C2A40214ECF038437B6922114E93B5F7" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_C1167AE0833BC902758E22114E911A72" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_C2A40214ECF038437B6922114E93B5F7" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedExcessPurchasePriceOverNetTangibleAssetsAcquired" xlink:label="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedExcessPurchasePriceOverNetTangibleAssetsAcquired_6F7D1CB735D8B54A2D2022114E93A73C" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_C1167AE0833BC902758E22114E911A72" xlink:to="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedExcessPurchasePriceOverNetTangibleAssetsAcquired_6F7D1CB735D8B54A2D2022114E93A73C" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedAllocationofExcessPurchasePriceAbstract" xlink:label="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedAllocationofExcessPurchasePriceAbstract_A14FBF9FCB0F76C2D05B22114E93DBD5" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_C1167AE0833BC902758E22114E911A72" xlink:to="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedAllocationofExcessPurchasePriceAbstract_A14FBF9FCB0F76C2D05B22114E93DBD5" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_BDE43B84814B1A6BDBAF22114E935BAA" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedAllocationofExcessPurchasePriceAbstract_A14FBF9FCB0F76C2D05B22114E93DBD5" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_BDE43B84814B1A6BDBAF22114E935BAA" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets_336CE209F979E7415F6322114E939F76" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedAllocationofExcessPurchasePriceAbstract_A14FBF9FCB0F76C2D05B22114E93DBD5" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets_336CE209F979E7415F6322114E939F76" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_F2F58E72E1389AD673CF22114E93C66C" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedAllocationofExcessPurchasePriceAbstract_A14FBF9FCB0F76C2D05B22114E93DBD5" xlink:to="loc_us-gaap_Goodwill_F2F58E72E1389AD673CF22114E93C66C" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/AcquisitionsDetailsTextual" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_D20302022EE3F049B472855BB7260BBC" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_BB603AFA1FF7F114C98B855BB7251275" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_D20302022EE3F049B472855BB7260BBC" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_BB603AFA1FF7F114C98B855BB7251275" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_DE0DA545CDAE8DEB48B0855BB72592DA" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_BB603AFA1FF7F114C98B855BB7251275" xlink:to="loc_us-gaap_RangeAxis_DE0DA545CDAE8DEB48B0855BB72592DA" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_0E7FF6C21E5C691B3E3F855BB725B978_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_DE0DA545CDAE8DEB48B0855BB72592DA" xlink:to="loc_us-gaap_RangeMember_0E7FF6C21E5C691B3E3F855BB725B978_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_0E7FF6C21E5C691B3E3F855BB725B978" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_DE0DA545CDAE8DEB48B0855BB72592DA" xlink:to="loc_us-gaap_RangeMember_0E7FF6C21E5C691B3E3F855BB725B978" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_9A3F3C17766FE4382FF6855BB726BFCD" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_0E7FF6C21E5C691B3E3F855BB725B978" xlink:to="loc_us-gaap_MinimumMember_9A3F3C17766FE4382FF6855BB726BFCD" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_2275549EEF348C20FC6F855BB7260BB5" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_0E7FF6C21E5C691B3E3F855BB725B978" xlink:to="loc_us-gaap_MaximumMember_2275549EEF348C20FC6F855BB7260BB5" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_B4C204A9A99161BAD407855BB726990E" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_BB603AFA1FF7F114C98B855BB7251275" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_B4C204A9A99161BAD407855BB726990E" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_E2BF2DCCCB8FA2459D3E855BB726428A_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_B4C204A9A99161BAD407855BB726990E" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_E2BF2DCCCB8FA2459D3E855BB726428A_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_E2BF2DCCCB8FA2459D3E855BB726428A" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_B4C204A9A99161BAD407855BB726990E" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_E2BF2DCCCB8FA2459D3E855BB726428A" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SelectiveInsuranceCompanyOfAmericaSelfInsuredPooledGroupMember" xlink:label="loc_afg_SelectiveInsuranceCompanyOfAmericaSelfInsuredPooledGroupMember_BDC4F4C608B4DF0AB567855BB7260751" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_E2BF2DCCCB8FA2459D3E855BB726428A" xlink:to="loc_afg_SelectiveInsuranceCompanyOfAmericaSelfInsuredPooledGroupMember_BDC4F4C608B4DF0AB567855BB7260751" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SummitHoldingSoutheastIncMember" xlink:label="loc_afg_SummitHoldingSoutheastIncMember_328C5034C91BD0C88423855BB7260C0F" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_E2BF2DCCCB8FA2459D3E855BB726428A" xlink:to="loc_afg_SummitHoldingSoutheastIncMember_328C5034C91BD0C88423855BB7260C0F" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PaymentsToAcquireBusinessesGross" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesGross_3E53EA4CED30E7805C1B855BB726AAC3" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_D20302022EE3F049B472855BB7260BBC" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesGross_3E53EA4CED30E7805C1B855BB726AAC3" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_PremiumsWrittenGrossInForce" xlink:label="loc_afg_PremiumsWrittenGrossInForce_1161FDBC8BB8DEE7317F855BB7263F1A" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_D20302022EE3F049B472855BB7260BBC" xlink:to="loc_afg_PremiumsWrittenGrossInForce_1161FDBC8BB8DEE7317F855BB7263F1A" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_CapitalContributionsToSubsidiaries" xlink:label="loc_afg_CapitalContributionsToSubsidiaries_8382312938C4439906CF855BB7269DCE" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_D20302022EE3F049B472855BB7260BBC" xlink:to="loc_afg_CapitalContributionsToSubsidiaries_8382312938C4439906CF855BB7269DCE" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_CapitalInvestmentInSubsidiariesTotal" xlink:label="loc_afg_CapitalInvestmentInSubsidiariesTotal_D6FA08627406F0307103855BB726C819" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_D20302022EE3F049B472855BB7260BBC" xlink:to="loc_afg_CapitalInvestmentInSubsidiariesTotal_D6FA08627406F0307103855BB726C819" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PremiumsWrittenNet" xlink:label="loc_us-gaap_PremiumsWrittenNet_5263C54F39964D073DFE855BB7269A35" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_D20302022EE3F049B472855BB7260BBC" xlink:to="loc_us-gaap_PremiumsWrittenNet_5263C54F39964D073DFE855BB7269A35" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PremiumsEarnedNet" xlink:label="loc_us-gaap_PremiumsEarnedNet_B6D04A419D1B1738D665855BB7262901" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_D20302022EE3F049B472855BB7260BBC" xlink:to="loc_us-gaap_PremiumsEarnedNet_B6D04A419D1B1738D665855BB7262901" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts" xlink:label="loc_us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts_E12F696189FEDBB26436855BB7265E4D" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_D20302022EE3F049B472855BB7260BBC" xlink:to="loc_us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts_E12F696189FEDBB26436855BB7265E4D" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIndefiniteLivedIntangibleAssets" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIndefiniteLivedIntangibleAssets_956EF36E3D92CC7B96C2855BB72632F6" xlink:type="locator" />
    <definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_D20302022EE3F049B472855BB7260BBC" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIndefiniteLivedIntangibleAssets_956EF36E3D92CC7B96C2855BB72632F6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_5B9E7417567ED03BC14F855BB726F16D" xlink:type="locator" />
    <definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_D20302022EE3F049B472855BB7260BBC" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_5B9E7417567ED03BC14F855BB726F16D" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife" xlink:label="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_13F423BCA116956426B2855BB727561D" xlink:type="locator" />
    <definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_D20302022EE3F049B472855BB7260BBC" xlink:to="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_13F423BCA116956426B2855BB727561D" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_B957EED990352458BBC6855BB727B9C7" xlink:type="locator" />
    <definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_D20302022EE3F049B472855BB7260BBC" xlink:to="loc_us-gaap_Goodwill_B957EED990352458BBC6855BB727B9C7" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/AcquisitionsTables" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/ConsolidatedBalanceSheetUnaudited" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/ConsolidatedBalanceSheetUnauditedParenthetical" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/ConsolidatedStatementOfCashFlowsUnaudited" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/ConsolidatedStatementOfChangesInEquityUnaudited" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaap_StatementLineItems_05C87FC947C5996A01E475F55DB8B26F" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable_50EF4A2389569338053475F55DB84C82" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_05C87FC947C5996A01E475F55DB8B26F" xlink:to="loc_us-gaap_StatementTable_50EF4A2389569338053475F55DB84C82" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_65697AF09693944784F575F55DB8BD11" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_50EF4A2389569338053475F55DB84C82" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_65697AF09693944784F575F55DB8BD11" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_46A667DBE22358592FC875F55DB8B351_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_65697AF09693944784F575F55DB8BD11" xlink:to="loc_us-gaap_EquityComponentDomain_46A667DBE22358592FC875F55DB8B351_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_46A667DBE22358592FC875F55DB8B351" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_65697AF09693944784F575F55DB8BD11" xlink:to="loc_us-gaap_EquityComponentDomain_46A667DBE22358592FC875F55DB8B351" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember_F2D0F4A1EC2D895D471D75F55DB84047" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_46A667DBE22358592FC875F55DB8B351" xlink:to="loc_us-gaap_CommonStockMember_F2D0F4A1EC2D895D471D75F55DB84047" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember" xlink:label="loc_us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember_E8ACF981B21ED43914DC75F55DB85850" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_46A667DBE22358592FC875F55DB8B351" xlink:to="loc_us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember_E8ACF981B21ED43914DC75F55DB85850" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RetainedEarningsAppropriatedMember" xlink:label="loc_us-gaap_RetainedEarningsAppropriatedMember_5EC1420D97D7D3B9228675F55DB85D4B" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_46A667DBE22358592FC875F55DB8B351" xlink:to="loc_us-gaap_RetainedEarningsAppropriatedMember_5EC1420D97D7D3B9228675F55DB85D4B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RetainedEarningsUnappropriatedMember" xlink:label="loc_us-gaap_RetainedEarningsUnappropriatedMember_8407A0CB1787ECDA6D7775F55DB89D12" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_46A667DBE22358592FC875F55DB8B351" xlink:to="loc_us-gaap_RetainedEarningsUnappropriatedMember_8407A0CB1787ECDA6D7775F55DB89D12" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_10D58411E8403A601C2F75F55DB8EF82" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_46A667DBE22358592FC875F55DB8B351" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_10D58411E8403A601C2F75F55DB8EF82" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ParentMember" xlink:label="loc_us-gaap_ParentMember_6490B52A96905262063275F55DB89098" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_46A667DBE22358592FC875F55DB8B351" xlink:to="loc_us-gaap_ParentMember_6490B52A96905262063275F55DB89098" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NoncontrollingInterestMember" xlink:label="loc_us-gaap_NoncontrollingInterestMember_5EE21DEAFA137CD1F1BF75F55DB8AA20" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_46A667DBE22358592FC875F55DB8B351" xlink:to="loc_us-gaap_NoncontrollingInterestMember_5EE21DEAFA137CD1F1BF75F55DB8AA20" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_1D02BCCAD650ABCB9AFF75F55DB87BE3" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_05C87FC947C5996A01E475F55DB8B26F" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_1D02BCCAD650ABCB9AFF75F55DB87BE3" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_C6CC458207B6ED7008AC75F55DB87A6B" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_05C87FC947C5996A01E475F55DB8B26F" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_C6CC458207B6ED7008AC75F55DB87A6B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaap_ProfitLoss_0C1725CB21E1BBE022E975F55DB842D5" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_05C87FC947C5996A01E475F55DB8B26F" xlink:to="loc_us-gaap_ProfitLoss_0C1725CB21E1BBE022E975F55DB842D5" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_EA5427DE3656BA2A46C075F55DB898E4" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_05C87FC947C5996A01E475F55DB8B26F" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_EA5427DE3656BA2A46C075F55DB898E4" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AllocationOfLossesOfManagedInvestmentEntities" xlink:label="loc_afg_AllocationOfLossesOfManagedInvestmentEntities_6326667DD4056ADB3D9E75F55DB8D67A" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_05C87FC947C5996A01E475F55DB8B26F" xlink:to="loc_afg_AllocationOfLossesOfManagedInvestmentEntities_6326667DD4056ADB3D9E75F55DB8D67A" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DividendsCommonStockCash" xlink:label="loc_us-gaap_DividendsCommonStockCash_A7F4C6787D529AA30A5B75F55DB8287A" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_05C87FC947C5996A01E475F55DB8B26F" xlink:to="loc_us-gaap_DividendsCommonStockCash_A7F4C6787D529AA30A5B75F55DB8287A" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SharesIssuedAbstract" xlink:label="loc_afg_SharesIssuedAbstract_C4CB7FAE4AA04A45C48B75F55DB84D55" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_05C87FC947C5996A01E475F55DB8B26F" xlink:to="loc_afg_SharesIssuedAbstract_C4CB7FAE4AA04A45C48B75F55DB84D55" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_511A9F3E13EFE255AE1B75F55DB861A9" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_SharesIssuedAbstract_C4CB7FAE4AA04A45C48B75F55DB84D55" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_511A9F3E13EFE255AE1B75F55DB861A9" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_4A97876CD60C66B93E6475F55DB8445F" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_SharesIssuedAbstract_C4CB7FAE4AA04A45C48B75F55DB84D55" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_4A97876CD60C66B93E6475F55DB8445F" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_9C8269C6ACEF1CFA9D4475F55DB8FB31" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_SharesIssuedAbstract_C4CB7FAE4AA04A45C48B75F55DB84D55" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_9C8269C6ACEF1CFA9D4475F55DB8FB31" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_FE3D330243E30590E76F75F55DB86395" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_SharesIssuedAbstract_C4CB7FAE4AA04A45C48B75F55DB84D55" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_FE3D330243E30590E76F75F55DB86395" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesDividendReinvestmentPlan" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesDividendReinvestmentPlan_CECDE7E0D57AF5B23D5B75F55DB8FD0F" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_SharesIssuedAbstract_C4CB7FAE4AA04A45C48B75F55DB84D55" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesDividendReinvestmentPlan_CECDE7E0D57AF5B23D5B75F55DB8FD0F" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan_00CC476E58CCF5CB75B575F55DB8E6A9" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_SharesIssuedAbstract_C4CB7FAE4AA04A45C48B75F55DB84D55" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan_00CC476E58CCF5CB75B575F55DB8E6A9" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_62F021238E17B4EF926875F55DB899F8" xlink:type="locator" />
    <definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_05C87FC947C5996A01E475F55DB8B26F" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_62F021238E17B4EF926875F55DB899F8" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodShares" xlink:label="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_07A9638B15A79011174275F55DB842AC" xlink:type="locator" />
    <definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_05C87FC947C5996A01E475F55DB8B26F" xlink:to="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_07A9638B15A79011174275F55DB842AC" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodValue" xlink:label="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_5477ADFFF0EAD2DEB69B75F55DB83F2F" xlink:type="locator" />
    <definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_05C87FC947C5996A01E475F55DB8B26F" xlink:to="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_5477ADFFF0EAD2DEB69B75F55DB83F2F" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_StockRepurchasedSharesExchangedInStockCompensationPlansShares" xlink:label="loc_afg_StockRepurchasedSharesExchangedInStockCompensationPlansShares_2E956B6F19171123F3E075F55DB8B9FD" xlink:type="locator" />
    <definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_05C87FC947C5996A01E475F55DB8B26F" xlink:to="loc_afg_StockRepurchasedSharesExchangedInStockCompensationPlansShares_2E956B6F19171123F3E075F55DB8B9FD" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_StockRepurchasedSharesExchangedInStockCompensationPlansValue" xlink:label="loc_afg_StockRepurchasedSharesExchangedInStockCompensationPlansValue_B1709852AE73223816B175F55DB8BE73" xlink:type="locator" />
    <definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_05C87FC947C5996A01E475F55DB8B26F" xlink:to="loc_afg_StockRepurchasedSharesExchangedInStockCompensationPlansValue_B1709852AE73223816B175F55DB8BE73" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockholdersEquityOther" xlink:label="loc_us-gaap_StockholdersEquityOther_488B6B00D056485F57B075F55DB8E40F" xlink:type="locator" />
    <definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_05C87FC947C5996A01E475F55DB8B26F" xlink:to="loc_us-gaap_StockholdersEquityOther_488B6B00D056485F57B075F55DB8E40F" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/ConsolidatedStatementOfComprehensiveIncomeUnaudited" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/ConsolidatedStatementOfEarningsUnaudited" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/Contingencies" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/ContingenciesDetails" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/DeferredPolicyAcquisitionCosts" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/DeferredPolicyAcquisitionCostsDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_1271F82C0EDBA7A6D32486AFFD257804" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_5885AF826EA9A770B02A86AFFD25C11F" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_1271F82C0EDBA7A6D32486AFFD257804" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_5885AF826EA9A770B02A86AFFD25C11F" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_DF5912148480E21DDF8C86AFFD25C251" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_5885AF826EA9A770B02A86AFFD25C11F" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_DF5912148480E21DDF8C86AFFD25C251" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_032B81140AC575E3201386AFFD25212E_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_DF5912148480E21DDF8C86AFFD25C251" xlink:to="loc_us-gaap_SegmentDomain_032B81140AC575E3201386AFFD25212E_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_032B81140AC575E3201386AFFD25212E" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_DF5912148480E21DDF8C86AFFD25C251" xlink:to="loc_us-gaap_SegmentDomain_032B81140AC575E3201386AFFD25212E" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_PropertyAndCasualtyInsuranceMember" xlink:label="loc_afg_PropertyAndCasualtyInsuranceMember_3C81489A2FC3BB1230FB86AFFD25B49A" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_032B81140AC575E3201386AFFD25212E" xlink:to="loc_afg_PropertyAndCasualtyInsuranceMember_3C81489A2FC3BB1230FB86AFFD25B49A" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AnnuityLongtermCareandLifeMember" xlink:label="loc_afg_AnnuityLongtermCareandLifeMember_5772FABF9E09C981EFFA86AFFD25C159" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_032B81140AC575E3201386AFFD25212E" xlink:to="loc_afg_AnnuityLongtermCareandLifeMember_5772FABF9E09C981EFFA86AFFD25C159" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquiredAbstract" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquiredAbstract_29AFBBB6F756510686B086AFFD253AFC" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_1271F82C0EDBA7A6D32486AFFD257804" xlink:to="loc_us-gaap_DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquiredAbstract_29AFBBB6F756510686B086AFFD253AFC" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsRollForward" xlink:label="loc_us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsRollForward_6B4AAC2CE16ED89E5B4086AFFD2A48A7" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquiredAbstract_29AFBBB6F756510686B086AFFD253AFC" xlink:to="loc_us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsRollForward_6B4AAC2CE16ED89E5B4086AFFD2A48A7" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredPolicyAcquisitionCosts" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCosts_38162F5B9782E686A27186AFFD2A3849" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsRollForward_6B4AAC2CE16ED89E5B4086AFFD2A48A7" xlink:to="loc_us-gaap_DeferredPolicyAcquisitionCosts_38162F5B9782E686A27186AFFD2A3849" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredPolicyAcquisitionCostsAdditions" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCostsAdditions_F8B6EB88A9D31EC61D9686AFFD2A232F" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsRollForward_6B4AAC2CE16ED89E5B4086AFFD2A48A7" xlink:to="loc_us-gaap_DeferredPolicyAcquisitionCostsAdditions_F8B6EB88A9D31EC61D9686AFFD2A232F" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_DeferredPolicyAcquisitionCostsAmortizationExpensePeriodicAmortization" xlink:label="loc_afg_DeferredPolicyAcquisitionCostsAmortizationExpensePeriodicAmortization_7BC2A792802A856ED1C886AFFD2A0E41" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsRollForward_6B4AAC2CE16ED89E5B4086AFFD2A48A7" xlink:to="loc_afg_DeferredPolicyAcquisitionCostsAmortizationExpensePeriodicAmortization_7BC2A792802A856ED1C886AFFD2A0E41" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredPolicyAcquisitionCostAmortizationExpenseNetInvestmentGainsLosses" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCostAmortizationExpenseNetInvestmentGainsLosses_A5BCD905232BF8E29AA786AFFD2BC7A6" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsRollForward_6B4AAC2CE16ED89E5B4086AFFD2A48A7" xlink:to="loc_us-gaap_DeferredPolicyAcquisitionCostAmortizationExpenseNetInvestmentGainsLosses_A5BCD905232BF8E29AA786AFFD2BC7A6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredPolicyAcquisitionCostForeignCurrencyTranslationAdjustment" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCostForeignCurrencyTranslationAdjustment_7EC8D25E5F8869F8A2E186AFFD2BBE27" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsRollForward_6B4AAC2CE16ED89E5B4086AFFD2A48A7" xlink:to="loc_us-gaap_DeferredPolicyAcquisitionCostForeignCurrencyTranslationAdjustment_7EC8D25E5F8869F8A2E186AFFD2BBE27" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MovementInDeferredSalesInducementsRollForward" xlink:label="loc_us-gaap_MovementInDeferredSalesInducementsRollForward_02B7D3052CE78391D86686AFFD2BE6B5" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquiredAbstract_29AFBBB6F756510686B086AFFD253AFC" xlink:to="loc_us-gaap_MovementInDeferredSalesInducementsRollForward_02B7D3052CE78391D86686AFFD2BE6B5" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredSalesInducementsNet" xlink:label="loc_us-gaap_DeferredSalesInducementsNet_7E85B555A52AB4084FFF86AFFD2B64AF" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementInDeferredSalesInducementsRollForward_02B7D3052CE78391D86686AFFD2BE6B5" xlink:to="loc_us-gaap_DeferredSalesInducementsNet_7E85B555A52AB4084FFF86AFFD2B64AF" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredSalesInducementsAdditions" xlink:label="loc_us-gaap_DeferredSalesInducementsAdditions_A6CB0DD679694B3A3A5486AFFD2B540C" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementInDeferredSalesInducementsRollForward_02B7D3052CE78391D86686AFFD2BE6B5" xlink:to="loc_us-gaap_DeferredSalesInducementsAdditions_A6CB0DD679694B3A3A5486AFFD2B540C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredSalesInducementsAmortizationExpense" xlink:label="loc_us-gaap_DeferredSalesInducementsAmortizationExpense_FBF3A624E5CF92AAD2DC86AFFD2BA122" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementInDeferredSalesInducementsRollForward_02B7D3052CE78391D86686AFFD2BE6B5" xlink:to="loc_us-gaap_DeferredSalesInducementsAmortizationExpense_FBF3A624E5CF92AAD2DC86AFFD2BA122" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_DeferredSalesInducementsAmortizationExpenseNetInvestmentGainsLosses" xlink:label="loc_afg_DeferredSalesInducementsAmortizationExpenseNetInvestmentGainsLosses_9850BD8BECB8234B30DC86AFFD2BB7DC" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementInDeferredSalesInducementsRollForward_02B7D3052CE78391D86686AFFD2BE6B5" xlink:to="loc_afg_DeferredSalesInducementsAmortizationExpenseNetInvestmentGainsLosses_9850BD8BECB8234B30DC86AFFD2BB7DC" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MovementInPresentValueOfFutureInsuranceProfitsRollForward" xlink:label="loc_us-gaap_MovementInPresentValueOfFutureInsuranceProfitsRollForward_4555D6AE4972DE7944C286AFFD2B73FC" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquiredAbstract_29AFBBB6F756510686B086AFFD253AFC" xlink:to="loc_us-gaap_MovementInPresentValueOfFutureInsuranceProfitsRollForward_4555D6AE4972DE7944C286AFFD2B73FC" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ValueOfBusinessAcquiredVOBA" xlink:label="loc_us-gaap_ValueOfBusinessAcquiredVOBA_1216B3D5198DEF36C51B86AFFD2B7F4B" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementInPresentValueOfFutureInsuranceProfitsRollForward_4555D6AE4972DE7944C286AFFD2B73FC" xlink:to="loc_us-gaap_ValueOfBusinessAcquiredVOBA_1216B3D5198DEF36C51B86AFFD2B7F4B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PresentValueOfFutureInsuranceProfitsAmortizationExpense1" xlink:label="loc_us-gaap_PresentValueOfFutureInsuranceProfitsAmortizationExpense1_A3F8ABA4DBAFD68E4C8486AFFD2B5DD9" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementInPresentValueOfFutureInsuranceProfitsRollForward_4555D6AE4972DE7944C286AFFD2B73FC" xlink:to="loc_us-gaap_PresentValueOfFutureInsuranceProfitsAmortizationExpense1_A3F8ABA4DBAFD68E4C8486AFFD2B5DD9" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_MovementInUnrealizedRelatedToDeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsRollForward" xlink:label="loc_afg_MovementInUnrealizedRelatedToDeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsRollForward_615272D02D445A774DCB86AFFD2B7F54" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquiredAbstract_29AFBBB6F756510686B086AFFD253AFC" xlink:to="loc_afg_MovementInUnrealizedRelatedToDeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsRollForward_615272D02D445A774DCB86AFFD2B7F54" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_DeferredPolicyAcquisitionCostsandValueofBusinessAcquiredUnrealizedInvestmentGainLoss" xlink:label="loc_afg_DeferredPolicyAcquisitionCostsandValueofBusinessAcquiredUnrealizedInvestmentGainLoss_9B0D5C2FC25F1C31F07686AFFD2BA744" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_MovementInUnrealizedRelatedToDeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsRollForward_615272D02D445A774DCB86AFFD2B7F54" xlink:to="loc_afg_DeferredPolicyAcquisitionCostsandValueofBusinessAcquiredUnrealizedInvestmentGainLoss_9B0D5C2FC25F1C31F07686AFFD2BA744" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_DeferredPolicyAcquisitionCostsandValueofBusinessAcquiredUnrealizedInvestmentGainLossChangeinUnrealized" xlink:label="loc_afg_DeferredPolicyAcquisitionCostsandValueofBusinessAcquiredUnrealizedInvestmentGainLossChangeinUnrealized_D9DB64564914E91AC6F586AFFD2B9B0A" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_MovementInUnrealizedRelatedToDeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsRollForward_615272D02D445A774DCB86AFFD2B7F54" xlink:to="loc_afg_DeferredPolicyAcquisitionCostsandValueofBusinessAcquiredUnrealizedInvestmentGainLossChangeinUnrealized_D9DB64564914E91AC6F586AFFD2B9B0A" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsRollForward" xlink:label="loc_us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsRollForward_FD5BA023F3A1256972D086AFFD2C5D20" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquiredAbstract_29AFBBB6F756510686B086AFFD253AFC" xlink:to="loc_us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsRollForward_FD5BA023F3A1256972D086AFFD2C5D20" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquired" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquired_A1DB572D9286F0B47E4886AFFD2CAF82" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsRollForward_FD5BA023F3A1256972D086AFFD2C5D20" xlink:to="loc_us-gaap_DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquired_A1DB572D9286F0B47E4886AFFD2CAF82" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAdditions" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAdditions_7348A11A4D68B6B451C686AFFD2C3642" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsRollForward_FD5BA023F3A1256972D086AFFD2C5D20" xlink:to="loc_us-gaap_DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAdditions_7348A11A4D68B6B451C686AFFD2C3642" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAmortization1" xlink:label="loc_us-gaap_DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAmortization1_F4F1B13A72A55B0446E886AFFD2CB86E" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsRollForward_FD5BA023F3A1256972D086AFFD2C5D20" xlink:to="loc_us-gaap_DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAmortization1_F4F1B13A72A55B0446E886AFFD2CB86E" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAmortizationExpenseNetInvestmentGainsLosses" xlink:label="loc_afg_DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAmortizationExpenseNetInvestmentGainsLosses_00B4E9172E4FDB5F0AA386AFFD2CAAD9" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsRollForward_FD5BA023F3A1256972D086AFFD2C5D20" xlink:to="loc_afg_DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAmortizationExpenseNetInvestmentGainsLosses_00B4E9172E4FDB5F0AA386AFFD2CAAD9" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_DeferredPolicyAcquisitionCostAndPresentValueOfFutureProfitsForeignCurrencyTranslationAdjustment" xlink:label="loc_afg_DeferredPolicyAcquisitionCostAndPresentValueOfFutureProfitsForeignCurrencyTranslationAdjustment_D496C064E99881AB72A286AFFD2C4C0F" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsRollForward_FD5BA023F3A1256972D086AFFD2C5D20" xlink:to="loc_afg_DeferredPolicyAcquisitionCostAndPresentValueOfFutureProfitsForeignCurrencyTranslationAdjustment_D496C064E99881AB72A286AFFD2C4C0F" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_DeferredPolicyAcquisitionCostsandPresentValueofFutureProfitsChangeinUnrealizedInvestmentGainLoss" xlink:label="loc_afg_DeferredPolicyAcquisitionCostsandPresentValueofFutureProfitsChangeinUnrealizedInvestmentGainLoss_EFBE52E4F15B1F4B057F86AFFD2C39C8" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementAnalysisOfDeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsRollForward_FD5BA023F3A1256972D086AFFD2C5D20" xlink:to="loc_afg_DeferredPolicyAcquisitionCostsandPresentValueofFutureProfitsChangeinUnrealizedInvestmentGainLoss_EFBE52E4F15B1F4B057F86AFFD2C39C8" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/DeferredPolicyAcquisitionCostsDetailsTextual" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/DeferredPolicyAcquisitionCostsTables" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/Derivatives" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/DerivativesDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativesFairValueLineItems" xlink:label="loc_us-gaap_DerivativesFairValueLineItems_CA3FB00C60C1FDA7145422114E8050BB" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable" xlink:label="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_8A8199CADC99AB59EB6822114E7FFB01" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_CA3FB00C60C1FDA7145422114E8050BB" xlink:to="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_8A8199CADC99AB59EB6822114E7FFB01" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_HedgingDesignationAxis" xlink:label="loc_us-gaap_HedgingDesignationAxis_0A51E2CD73B74DFB66F922114E7F4E1C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_8A8199CADC99AB59EB6822114E7FFB01" xlink:to="loc_us-gaap_HedgingDesignationAxis_0A51E2CD73B74DFB66F922114E7F4E1C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_HedgingDesignationDomain" xlink:label="loc_us-gaap_HedgingDesignationDomain_075EB339541F2D35CC6522114E7F34B2_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_0A51E2CD73B74DFB66F922114E7F4E1C" xlink:to="loc_us-gaap_HedgingDesignationDomain_075EB339541F2D35CC6522114E7F34B2_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_HedgingDesignationDomain" xlink:label="loc_us-gaap_HedgingDesignationDomain_075EB339541F2D35CC6522114E7F34B2" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_0A51E2CD73B74DFB66F922114E7F4E1C" xlink:to="loc_us-gaap_HedgingDesignationDomain_075EB339541F2D35CC6522114E7F34B2" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NondesignatedMember" xlink:label="loc_us-gaap_NondesignatedMember_233739DBB9EFB66E59C422114E7FC503" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_075EB339541F2D35CC6522114E7F34B2" xlink:to="loc_us-gaap_NondesignatedMember_233739DBB9EFB66E59C422114E7FC503" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_C6C7F8679DFA2356705522114E7FB7AC" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_8A8199CADC99AB59EB6822114E7FFB01" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_C6C7F8679DFA2356705522114E7FB7AC" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_43D2E2016004EEDCE69F22114E7FA6D5_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_C6C7F8679DFA2356705522114E7FB7AC" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_43D2E2016004EEDCE69F22114E7FA6D5_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_43D2E2016004EEDCE69F22114E7FA6D5" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_C6C7F8679DFA2356705522114E7FB7AC" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_43D2E2016004EEDCE69F22114E7FA6D5" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_MortgageBackedSecuritiesWithEmbeddedDerivativesMember" xlink:label="loc_afg_MortgageBackedSecuritiesWithEmbeddedDerivativesMember_049D9DB2FD9D32AAD1BB22114E7F14C5" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_43D2E2016004EEDCE69F22114E7FA6D5" xlink:to="loc_afg_MortgageBackedSecuritiesWithEmbeddedDerivativesMember_049D9DB2FD9D32AAD1BB22114E7F14C5" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_WarrantMember" xlink:label="loc_us-gaap_WarrantMember_27E1A78CE3B5465186B822114E7FB0E6" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_43D2E2016004EEDCE69F22114E7FA6D5" xlink:to="loc_us-gaap_WarrantMember_27E1A78CE3B5465186B822114E7FB0E6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InterestRateSwaptionMember" xlink:label="loc_us-gaap_InterestRateSwaptionMember_DF9CE602DE5DC55FE33A22114E7F20E7" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_43D2E2016004EEDCE69F22114E7FA6D5" xlink:to="loc_us-gaap_InterestRateSwaptionMember_DF9CE602DE5DC55FE33A22114E7F20E7" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FixedIndexedAnnuitiesEmbeddedDerivativeMember" xlink:label="loc_afg_FixedIndexedAnnuitiesEmbeddedDerivativeMember_0B3EB6480E18C9F19E7422114E7FAC70" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_43D2E2016004EEDCE69F22114E7FA6D5" xlink:to="loc_afg_FixedIndexedAnnuitiesEmbeddedDerivativeMember_0B3EB6480E18C9F19E7422114E7FAC70" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_EquityIndexCallOptionsMember" xlink:label="loc_afg_EquityIndexCallOptionsMember_6193018C4C9EC79E0AFA22114E7FC4D6" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_43D2E2016004EEDCE69F22114E7FA6D5" xlink:to="loc_afg_EquityIndexCallOptionsMember_6193018C4C9EC79E0AFA22114E7FC4D6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherContractMember" xlink:label="loc_us-gaap_OtherContractMember_77A97717CA0D1FD8148F22114E7FCCB2" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_43D2E2016004EEDCE69F22114E7FA6D5" xlink:to="loc_us-gaap_OtherContractMember_77A97717CA0D1FD8148F22114E7FCCB2" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BalanceSheetLocationAxis" xlink:label="loc_us-gaap_BalanceSheetLocationAxis_D21D1BB40EF32A8F3D1722114E7F6BCD" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_8A8199CADC99AB59EB6822114E7FFB01" xlink:to="loc_us-gaap_BalanceSheetLocationAxis_D21D1BB40EF32A8F3D1722114E7F6BCD" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BalanceSheetLocationDomain" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_424A6D0594BDF5B727DC22114E802056_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_D21D1BB40EF32A8F3D1722114E7F6BCD" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_424A6D0594BDF5B727DC22114E802056_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_BalanceSheetLocationDomain" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_424A6D0594BDF5B727DC22114E802056" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_D21D1BB40EF32A8F3D1722114E7F6BCD" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_424A6D0594BDF5B727DC22114E802056" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FixedMaturitiesMember" xlink:label="loc_us-gaap_FixedMaturitiesMember_1009583323111F3DE26C22114E8017C4" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_424A6D0594BDF5B727DC22114E802056" xlink:to="loc_us-gaap_FixedMaturitiesMember_1009583323111F3DE26C22114E8017C4" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EquitySecuritiesMember" xlink:label="loc_us-gaap_EquitySecuritiesMember_29D19144B14C81CBE71822114E8052BF" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_424A6D0594BDF5B727DC22114E802056" xlink:to="loc_us-gaap_EquitySecuritiesMember_29D19144B14C81CBE71822114E8052BF" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherInvestmentsMember" xlink:label="loc_us-gaap_OtherInvestmentsMember_2E26F1FA6D441180799F22114E800F81" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_424A6D0594BDF5B727DC22114E802056" xlink:to="loc_us-gaap_OtherInvestmentsMember_2E26F1FA6D441180799F22114E800F81" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AnnuityBenefitsAccumulatedMember" xlink:label="loc_afg_AnnuityBenefitsAccumulatedMember_778A52A60D14A48C197622114E80AC32" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_424A6D0594BDF5B727DC22114E802056" xlink:to="loc_afg_AnnuityBenefitsAccumulatedMember_778A52A60D14A48C197622114E80AC32" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherLiabilitiesMember" xlink:label="loc_us-gaap_OtherLiabilitiesMember_E66979C31D10A873CFD922114E807C59" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_424A6D0594BDF5B727DC22114E802056" xlink:to="loc_us-gaap_OtherLiabilitiesMember_E66979C31D10A873CFD922114E807C59" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAbstract" xlink:label="loc_us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAbstract_D788358FDDB1452BDF6722114E809C4A" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_CA3FB00C60C1FDA7145422114E8050BB" xlink:to="loc_us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAbstract_D788358FDDB1452BDF6722114E809C4A" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral_A40C921F68BB3C3934EE22114E804F19" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAbstract_D788358FDDB1452BDF6722114E809C4A" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral_A40C921F68BB3C3934EE22114E804F19" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral_288D50FD138508FE40E222114E80A6D8" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAbstract_D788358FDDB1452BDF6722114E809C4A" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral_288D50FD138508FE40E222114E80A6D8" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/DerivativesDetails1" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_729FB482D1394291ED7A22114E30AD3B" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_2546BC7A1CC88327AD9822114E2E709B" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_729FB482D1394291ED7A22114E30AD3B" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_2546BC7A1CC88327AD9822114E2E709B" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_HedgingDesignationAxis" xlink:label="loc_us-gaap_HedgingDesignationAxis_A8B825C4FC8E7F50F4B122114E2F4157" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_2546BC7A1CC88327AD9822114E2E709B" xlink:to="loc_us-gaap_HedgingDesignationAxis_A8B825C4FC8E7F50F4B122114E2F4157" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_HedgingDesignationDomain" xlink:label="loc_us-gaap_HedgingDesignationDomain_309855FBBE905D3AA1DF22114E2F0376_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_A8B825C4FC8E7F50F4B122114E2F4157" xlink:to="loc_us-gaap_HedgingDesignationDomain_309855FBBE905D3AA1DF22114E2F0376_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_HedgingDesignationDomain" xlink:label="loc_us-gaap_HedgingDesignationDomain_309855FBBE905D3AA1DF22114E2F0376" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_A8B825C4FC8E7F50F4B122114E2F4157" xlink:to="loc_us-gaap_HedgingDesignationDomain_309855FBBE905D3AA1DF22114E2F0376" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NondesignatedMember" xlink:label="loc_us-gaap_NondesignatedMember_E8DAAD67B4148342605C22114E2F8FCD" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_309855FBBE905D3AA1DF22114E2F0376" xlink:to="loc_us-gaap_NondesignatedMember_E8DAAD67B4148342605C22114E2F8FCD" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_2A9517172ED125E9E56922114E2F8814" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_2546BC7A1CC88327AD9822114E2E709B" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_2A9517172ED125E9E56922114E2F8814" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_94133745746972DE825D22114E2FCFB4_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_2A9517172ED125E9E56922114E2F8814" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_94133745746972DE825D22114E2FCFB4_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_94133745746972DE825D22114E2FCFB4" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_2A9517172ED125E9E56922114E2F8814" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_94133745746972DE825D22114E2FCFB4" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_MortgageBackedSecuritiesWithEmbeddedDerivativesMember" xlink:label="loc_afg_MortgageBackedSecuritiesWithEmbeddedDerivativesMember_B62596FFDC4D6CA4016922114E2F4498" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_94133745746972DE825D22114E2FCFB4" xlink:to="loc_afg_MortgageBackedSecuritiesWithEmbeddedDerivativesMember_B62596FFDC4D6CA4016922114E2F4498" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_WarrantMember" xlink:label="loc_us-gaap_WarrantMember_9718041DC5CF88E2DF3D22114E2FC913" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_94133745746972DE825D22114E2FCFB4" xlink:to="loc_us-gaap_WarrantMember_9718041DC5CF88E2DF3D22114E2FC913" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InterestRateSwaptionMember" xlink:label="loc_us-gaap_InterestRateSwaptionMember_70142D12D5C5485E3B2F22114E2F02EE" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_94133745746972DE825D22114E2FCFB4" xlink:to="loc_us-gaap_InterestRateSwaptionMember_70142D12D5C5485E3B2F22114E2F02EE" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FixedIndexedAnnuitiesEmbeddedDerivativeMember" xlink:label="loc_afg_FixedIndexedAnnuitiesEmbeddedDerivativeMember_2541BA0C82D1739FF10022114E2F22A1" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_94133745746972DE825D22114E2FCFB4" xlink:to="loc_afg_FixedIndexedAnnuitiesEmbeddedDerivativeMember_2541BA0C82D1739FF10022114E2F22A1" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_EquityIndexCallOptionsMember" xlink:label="loc_afg_EquityIndexCallOptionsMember_E65B24DB185C2BB603F122114E2F86A2" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_94133745746972DE825D22114E2FCFB4" xlink:to="loc_afg_EquityIndexCallOptionsMember_E65B24DB185C2BB603F122114E2F86A2" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherContractMember" xlink:label="loc_us-gaap_OtherContractMember_BEE2B055BCDC46201C6D22114E2F254C" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_94133745746972DE825D22114E2FCFB4" xlink:to="loc_us-gaap_OtherContractMember_BEE2B055BCDC46201C6D22114E2F254C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_3D7AF5309397FFD996A422114E2F2CF9" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_2546BC7A1CC88327AD9822114E2E709B" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_3D7AF5309397FFD996A422114E2F2CF9" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_F9C144DBF93440BA32FD22114E2F4BF8_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_3D7AF5309397FFD996A422114E2F2CF9" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_F9C144DBF93440BA32FD22114E2F4BF8_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_F9C144DBF93440BA32FD22114E2F4BF8" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_3D7AF5309397FFD996A422114E2F2CF9" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_F9C144DBF93440BA32FD22114E2F4BF8" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_RealizedGainsLossesOnSecuritiesMember" xlink:label="loc_afg_RealizedGainsLossesOnSecuritiesMember_7725E29A56CB0C27FC0622114E2F6940" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_F9C144DBF93440BA32FD22114E2F4BF8" xlink:to="loc_afg_RealizedGainsLossesOnSecuritiesMember_7725E29A56CB0C27FC0622114E2F6940" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AnnuitybenefitsMember" xlink:label="loc_afg_AnnuitybenefitsMember_C98FC7F3DCD949CA834322114E308A20" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_F9C144DBF93440BA32FD22114E2F4BF8" xlink:to="loc_afg_AnnuitybenefitsMember_C98FC7F3DCD949CA834322114E308A20" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InvestmentIncomeMember" xlink:label="loc_us-gaap_InvestmentIncomeMember_E3EDFBF11D0C10C4393C22114E306497" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_F9C144DBF93440BA32FD22114E2F4BF8" xlink:to="loc_us-gaap_InvestmentIncomeMember_E3EDFBF11D0C10C4393C22114E306497" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeGainLossOnDerivativeNetAbstract" xlink:label="loc_us-gaap_DerivativeGainLossOnDerivativeNetAbstract_B87E4790D878D295ECBF22114E30A666" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_729FB482D1394291ED7A22114E30AD3B" xlink:to="loc_us-gaap_DerivativeGainLossOnDerivativeNetAbstract_B87E4790D878D295ECBF22114E30A666" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeGainLossOnDerivativeNet" xlink:label="loc_us-gaap_DerivativeGainLossOnDerivativeNet_660D6E782C4D7AA1C12022114E301E41" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeGainLossOnDerivativeNetAbstract_B87E4790D878D295ECBF22114E30A666" xlink:to="loc_us-gaap_DerivativeGainLossOnDerivativeNet_660D6E782C4D7AA1C12022114E301E41" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/DerivativesDetailsTextual" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_B4E96A727BCFD287E36A85C0E9132193" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_F82951B7E609AAACC43985C0E912379E" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_B4E96A727BCFD287E36A85C0E9132193" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_F82951B7E609AAACC43985C0E912379E" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_35195128470F239AFDBD85C0E912A3E5" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_F82951B7E609AAACC43985C0E912379E" xlink:to="loc_us-gaap_RangeAxis_35195128470F239AFDBD85C0E912A3E5" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_CA541F706F3F4A2C910085C0E91277C0_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_35195128470F239AFDBD85C0E912A3E5" xlink:to="loc_us-gaap_RangeMember_CA541F706F3F4A2C910085C0E91277C0_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_CA541F706F3F4A2C910085C0E91277C0" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_35195128470F239AFDBD85C0E912A3E5" xlink:to="loc_us-gaap_RangeMember_CA541F706F3F4A2C910085C0E91277C0" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_13F4738FA0210B7872D585C0E9127A7F" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_CA541F706F3F4A2C910085C0E91277C0" xlink:to="loc_us-gaap_MaximumMember_13F4738FA0210B7872D585C0E9127A7F" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_09821F8BC394DE12BC6B85C0E9136F8F" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_F82951B7E609AAACC43985C0E912379E" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_09821F8BC394DE12BC6B85C0E9136F8F" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_HedgingRelationshipDomain" xlink:label="loc_us-gaap_HedgingRelationshipDomain_8007E118A2EABFA14C8585C0E913A56C_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_09821F8BC394DE12BC6B85C0E9136F8F" xlink:to="loc_us-gaap_HedgingRelationshipDomain_8007E118A2EABFA14C8585C0E913A56C_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_HedgingRelationshipDomain" xlink:label="loc_us-gaap_HedgingRelationshipDomain_8007E118A2EABFA14C8585C0E913A56C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_09821F8BC394DE12BC6B85C0E9136F8F" xlink:to="loc_us-gaap_HedgingRelationshipDomain_8007E118A2EABFA14C8585C0E913A56C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CashFlowHedgingMember" xlink:label="loc_us-gaap_CashFlowHedgingMember_5A14B538F671DDDF604C85C0E9132B57" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_8007E118A2EABFA14C8585C0E913A56C" xlink:to="loc_us-gaap_CashFlowHedgingMember_5A14B538F671DDDF604C85C0E9132B57" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_HedgingDesignationAxis" xlink:label="loc_us-gaap_HedgingDesignationAxis_23B4566B2BA9D4FA5C5A85C0E913D25C" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_F82951B7E609AAACC43985C0E912379E" xlink:to="loc_us-gaap_HedgingDesignationAxis_23B4566B2BA9D4FA5C5A85C0E913D25C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_HedgingDesignationDomain" xlink:label="loc_us-gaap_HedgingDesignationDomain_C1588B53A05A2F0E0F6685C0E9139F96_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_23B4566B2BA9D4FA5C5A85C0E913D25C" xlink:to="loc_us-gaap_HedgingDesignationDomain_C1588B53A05A2F0E0F6685C0E9139F96_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_HedgingDesignationDomain" xlink:label="loc_us-gaap_HedgingDesignationDomain_C1588B53A05A2F0E0F6685C0E9139F96" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_23B4566B2BA9D4FA5C5A85C0E913D25C" xlink:to="loc_us-gaap_HedgingDesignationDomain_C1588B53A05A2F0E0F6685C0E9139F96" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NondesignatedMember" xlink:label="loc_us-gaap_NondesignatedMember_E7FBF4D0CDAC861E74C885C0E913736A" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_C1588B53A05A2F0E0F6685C0E9139F96" xlink:to="loc_us-gaap_NondesignatedMember_E7FBF4D0CDAC861E74C885C0E913736A" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DesignatedAsHedgingInstrumentMember" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_2D63A7525C0BE37CE0B085C0E9130536" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_C1588B53A05A2F0E0F6685C0E9139F96" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_2D63A7525C0BE37CE0B085C0E9130536" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_53472D4FA29D2B40DED885C0E9137B38" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_F82951B7E609AAACC43985C0E912379E" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_53472D4FA29D2B40DED885C0E9137B38" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_387CBF89AD7AB16DF25F85C0E9136D8E_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_53472D4FA29D2B40DED885C0E9137B38" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_387CBF89AD7AB16DF25F85C0E9136D8E_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_387CBF89AD7AB16DF25F85C0E9136D8E" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_53472D4FA29D2B40DED885C0E9137B38" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_387CBF89AD7AB16DF25F85C0E9136D8E" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InterestRateSwaptionMember" xlink:label="loc_us-gaap_InterestRateSwaptionMember_4AAF515993B946EDE7C385C0E913258C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_387CBF89AD7AB16DF25F85C0E9136D8E" xlink:to="loc_us-gaap_InterestRateSwaptionMember_4AAF515993B946EDE7C385C0E913258C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeAssetNotionalAmount" xlink:label="loc_us-gaap_DerivativeAssetNotionalAmount_E14D5E49E682FE9F9E0E85C0E913A6C4" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_B4E96A727BCFD287E36A85C0E9132193" xlink:to="loc_us-gaap_DerivativeAssetNotionalAmount_E14D5E49E682FE9F9E0E85C0E913A6C4" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_CumulativePaymentstoPurchaseDerivatives" xlink:label="loc_afg_CumulativePaymentstoPurchaseDerivatives_901F2EB2E86AAB7AC2F285C0E9133122" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_B4E96A727BCFD287E36A85C0E9132193" xlink:to="loc_afg_CumulativePaymentstoPurchaseDerivatives_901F2EB2E86AAB7AC2F285C0E9133122" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_IndexedAnnuitiesAsPercentageOfAnnuityBenefits" xlink:label="loc_afg_IndexedAnnuitiesAsPercentageOfAnnuityBenefits_8A5079AAAF7D168CE01B85C0E9130F62" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_B4E96A727BCFD287E36A85C0E9132193" xlink:to="loc_afg_IndexedAnnuitiesAsPercentageOfAnnuityBenefits_8A5079AAAF7D168CE01B85C0E9130F62" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeCollateralRightToReclaimCash" xlink:label="loc_us-gaap_DerivativeCollateralRightToReclaimCash_56C4D63CDE080692675B85C0EDBF73DE" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_B4E96A727BCFD287E36A85C0E9132193" xlink:to="loc_us-gaap_DerivativeCollateralRightToReclaimCash_56C4D63CDE080692675B85C0EDBF73DE" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/invest/2013/invest-2013-01-31.xsd#invest_DerivativeNotionalAmount" xlink:label="loc_invest_DerivativeNotionalAmount_E7C06361F4CE20BCE1D985C0E9140FE2" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_B4E96A727BCFD287E36A85C0E9132193" xlink:to="loc_invest_DerivativeNotionalAmount_E7C06361F4CE20BCE1D985C0E9140FE2" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeFairValueOfDerivativeNet" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeNet_36724ED2E2CD4232D48A85C0E914C27C" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_B4E96A727BCFD287E36A85C0E9132193" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeNet_36724ED2E2CD4232D48A85C0E914C27C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet_866EE5BE60B5AAF7736785C0E914F2A1" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_B4E96A727BCFD287E36A85C0E9132193" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet_866EE5BE60B5AAF7736785C0E914F2A1" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/DerivativesTables" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/DocumentAndEntityInformation" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/FairValueMeasurements" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/FairValueMeasurementsDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_9A9C6FD8C38A366315C022114F6E6056" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_9AC2C9FE1A5C7A43316B22114F67E070" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_9A9C6FD8C38A366315C022114F6E6056" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_9AC2C9FE1A5C7A43316B22114F67E070" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_CD6B6018C99AB318077B22114F6D842C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_9AC2C9FE1A5C7A43316B22114F67E070" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_CD6B6018C99AB318077B22114F6D842C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C518BB1C102E55D47BFC22114F6D1653_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_CD6B6018C99AB318077B22114F6D842C" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C518BB1C102E55D47BFC22114F6D1653_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C518BB1C102E55D47BFC22114F6D1653" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_CD6B6018C99AB318077B22114F6D842C" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C518BB1C102E55D47BFC22114F6D1653" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueInputsLevel1Member" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_687A87ACF9E3D0AB89B122114F6D1153" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C518BB1C102E55D47BFC22114F6D1653" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_687A87ACF9E3D0AB89B122114F6D1153" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueInputsLevel2Member" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_D03C877060F0AC9C71B722114F6D1EDA" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C518BB1C102E55D47BFC22114F6D1653" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_D03C877060F0AC9C71B722114F6D1EDA" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueInputsLevel3Member" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_54E6053964A2F922BAA122114F6D0734" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C518BB1C102E55D47BFC22114F6D1653" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_54E6053964A2F922BAA122114F6D0734" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueByAssetClassAxis" xlink:label="loc_us-gaap_FairValueByAssetClassAxis_A1358EB39BE200BC234B22114F6D465F" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_9AC2C9FE1A5C7A43316B22114F67E070" xlink:to="loc_us-gaap_FairValueByAssetClassAxis_A1358EB39BE200BC234B22114F6D465F" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_465BD19958B68E65DDAB22114F6D008F_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_A1358EB39BE200BC234B22114F6D465F" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_465BD19958B68E65DDAB22114F6D008F_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_465BD19958B68E65DDAB22114F6D008F" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_A1358EB39BE200BC234B22114F6D465F" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_465BD19958B68E65DDAB22114F6D008F" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_USTreasuryAndGovernmentMember" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_08557896F4717D39C01822114F6D0F32" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_465BD19958B68E65DDAB22114F6D008F" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_08557896F4717D39C01822114F6D0F32" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_50DE20496D532E3A51F922114F6D4713" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_465BD19958B68E65DDAB22114F6D008F" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_50DE20496D532E3A51F922114F6D4713" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember" xlink:label="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_607098380DEF36E9D4A222114F6D6DDB" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_465BD19958B68E65DDAB22114F6D008F" xlink:to="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_607098380DEF36E9D4A222114F6D6DDB" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ResidentialMortgageBackedSecuritiesMember" xlink:label="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_28EF60EE2526CAA891CB22114F6D13F6" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_465BD19958B68E65DDAB22114F6D008F" xlink:to="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_28EF60EE2526CAA891CB22114F6D13F6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CommercialMortgageBackedSecuritiesMember" xlink:label="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_4AC62B4D82ED79F484A622114F6D1F23" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_465BD19958B68E65DDAB22114F6D008F" xlink:to="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_4AC62B4D82ED79F484A622114F6D1F23" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AssetBackedSecuritiesMember" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_9F6B58526BCCAD830F4B22114F6D54E5" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_465BD19958B68E65DDAB22114F6D008F" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_9F6B58526BCCAD830F4B22114F6D54E5" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CorporateDebtSecuritiesMember" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_6AA4D6938A04FB794C3E22114F6E020A" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_465BD19958B68E65DDAB22114F6D008F" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_6AA4D6938A04FB794C3E22114F6E020A" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FixedMaturitiesMember" xlink:label="loc_us-gaap_FixedMaturitiesMember_954103FF006DFE95F9F322114F6E5A3F" xlink:type="locator" />
    <definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_465BD19958B68E65DDAB22114F6D008F" xlink:to="loc_us-gaap_FixedMaturitiesMember_954103FF006DFE95F9F322114F6E5A3F" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EquitySecuritiesMember" xlink:label="loc_us-gaap_EquitySecuritiesMember_0692A3661E972C56966322114F6E6FE4" xlink:type="locator" />
    <definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_465BD19958B68E65DDAB22114F6D008F" xlink:to="loc_us-gaap_EquitySecuritiesMember_0692A3661E972C56966322114F6E6FE4" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueByLiabilityClassAxis" xlink:label="loc_us-gaap_FairValueByLiabilityClassAxis_3634224742341FC2668822114F6E8308" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_9AC2C9FE1A5C7A43316B22114F67E070" xlink:to="loc_us-gaap_FairValueByLiabilityClassAxis_3634224742341FC2668822114F6E8308" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_6F2342F53B4AA4E8091922114F6EF9D3_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByLiabilityClassAxis_3634224742341FC2668822114F6E8308" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_6F2342F53B4AA4E8091922114F6EF9D3_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_6F2342F53B4AA4E8091922114F6EF9D3" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByLiabilityClassAxis_3634224742341FC2668822114F6E8308" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_6F2342F53B4AA4E8091922114F6EF9D3" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AnnuityBenefitsAccumulatedMember" xlink:label="loc_afg_AnnuityBenefitsAccumulatedMember_6BB4FB3CCBFBCC55FACE22114F6E1F52" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_6F2342F53B4AA4E8091922114F6EF9D3" xlink:to="loc_afg_AnnuityBenefitsAccumulatedMember_6BB4FB3CCBFBCC55FACE22114F6E1F52" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherLiabilitiesMember" xlink:label="loc_us-gaap_OtherLiabilitiesMember_6EC9BAC6B9552CC325D022114F6E9174" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_6F2342F53B4AA4E8091922114F6EF9D3" xlink:to="loc_us-gaap_OtherLiabilitiesMember_6EC9BAC6B9552CC325D022114F6E9174" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisAbstract" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisAbstract_098C0E5DD335324796A722114F6EDA2D" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_9A9C6FD8C38A366315C022114F6E6056" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisAbstract_098C0E5DD335324796A722114F6EDA2D" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AssetsFairValueDisclosureAbstract" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_366C124558D1A6018F9822114F6E6AA6" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisAbstract_098C0E5DD335324796A722114F6EDA2D" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_366C124558D1A6018F9822114F6E6AA6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecurities" xlink:label="loc_us-gaap_AvailableForSaleSecurities_ED7F18B546D02A80513722114F6E7609" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_366C124558D1A6018F9822114F6E6AA6" xlink:to="loc_us-gaap_AvailableForSaleSecurities_ED7F18B546D02A80513722114F6E7609" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_TradingSecurities" xlink:label="loc_us-gaap_TradingSecurities_8434CFE5A95D100C269F22114F6EED5B" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_366C124558D1A6018F9822114F6E6AA6" xlink:to="loc_us-gaap_TradingSecurities_8434CFE5A95D100C269F22114F6EED5B" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AssetsOfManagedInvestmentEntitiesFairValueDisclosure" xlink:label="loc_afg_AssetsOfManagedInvestmentEntitiesFairValueDisclosure_6B04CF5EE72E6F37A25E22114F6E9FF1" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_366C124558D1A6018F9822114F6E6AA6" xlink:to="loc_afg_AssetsOfManagedInvestmentEntitiesFairValueDisclosure_6B04CF5EE72E6F37A25E22114F6E9FF1" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_VariableAnnuityAssetsFairValueDisclosure" xlink:label="loc_afg_VariableAnnuityAssetsFairValueDisclosure_9439C879DB22FE35B75D22114F6EA1C7" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_366C124558D1A6018F9822114F6E6AA6" xlink:to="loc_afg_VariableAnnuityAssetsFairValueDisclosure_9439C879DB22FE35B75D22114F6EA1C7" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_OtherInvestmentsFairValueDisclosure" xlink:label="loc_afg_OtherInvestmentsFairValueDisclosure_323F6C81A8BBBC8473E022114F6E78E9" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_366C124558D1A6018F9822114F6E6AA6" xlink:to="loc_afg_OtherInvestmentsFairValueDisclosure_323F6C81A8BBBC8473E022114F6E78E9" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AssetsFairValueDisclosure" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_0949BB42FB2D1C1E29F122114F6F68D5" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_366C124558D1A6018F9822114F6E6AA6" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_0949BB42FB2D1C1E29F122114F6F68D5" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LiabilitiesFairValueDisclosureAbstract" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_14643B072E46E796FED322114F6F83A9" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisAbstract_098C0E5DD335324796A722114F6EDA2D" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_14643B072E46E796FED322114F6F83A9" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_LiabilitiesOfManagedInvestmentEntitiesFairValueDisclosure" xlink:label="loc_afg_LiabilitiesOfManagedInvestmentEntitiesFairValueDisclosure_41606BE615F337C2086522114F6FA926" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_14643B072E46E796FED322114F6F83A9" xlink:to="loc_afg_LiabilitiesOfManagedInvestmentEntitiesFairValueDisclosure_41606BE615F337C2086522114F6FA926" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeLiabilities" xlink:label="loc_us-gaap_DerivativeLiabilities_B00E96237FCC768FC1DF22114F6F2DEF" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_14643B072E46E796FED322114F6F83A9" xlink:to="loc_us-gaap_DerivativeLiabilities_B00E96237FCC768FC1DF22114F6F2DEF" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LiabilitiesFairValueDisclosure" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure_E537E94227181DBA6EAC22114F6FBA02" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_14643B072E46E796FED322114F6F83A9" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosure_E537E94227181DBA6EAC22114F6FBA02" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/FairValueMeasurementsDetails1" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueInputsLiabilitiesQuantitativeInformationLineItems" xlink:label="loc_us-gaap_FairValueInputsLiabilitiesQuantitativeInformationLineItems_B9399D797A4DA12DBE8622114F4D15AC" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueInputsAssetsQuantitativeInformationTable" xlink:label="loc_us-gaap_FairValueInputsAssetsQuantitativeInformationTable_DB561E2845B979725E1722114F4C1182" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueInputsLiabilitiesQuantitativeInformationLineItems_B9399D797A4DA12DBE8622114F4D15AC" xlink:to="loc_us-gaap_FairValueInputsAssetsQuantitativeInformationTable_DB561E2845B979725E1722114F4C1182" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_B7316C29A2C7C9762DA822114F4CF787" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueInputsAssetsQuantitativeInformationTable_DB561E2845B979725E1722114F4C1182" xlink:to="loc_us-gaap_RangeAxis_B7316C29A2C7C9762DA822114F4CF787" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_A2EAC7C229415E2D04B222114F4C3955_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_B7316C29A2C7C9762DA822114F4CF787" xlink:to="loc_us-gaap_RangeMember_A2EAC7C229415E2D04B222114F4C3955_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_A2EAC7C229415E2D04B222114F4C3955" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_B7316C29A2C7C9762DA822114F4CF787" xlink:to="loc_us-gaap_RangeMember_A2EAC7C229415E2D04B222114F4C3955" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_7E68D5A6956D9027CCB222114F4CBD13" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_A2EAC7C229415E2D04B222114F4C3955" xlink:to="loc_us-gaap_MinimumMember_7E68D5A6956D9027CCB222114F4CBD13" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_4A1B450BF10714090C2C22114F4D05BE" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_A2EAC7C229415E2D04B222114F4C3955" xlink:to="loc_us-gaap_MaximumMember_4A1B450BF10714090C2C22114F4D05BE" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_37F36C50189328138FA022114F4D0668" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueInputsAssetsQuantitativeInformationTable_DB561E2845B979725E1722114F4C1182" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_37F36C50189328138FA022114F4D0668" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_BDE527A3BA1583DD596D22114F4D1AE3_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_37F36C50189328138FA022114F4D0668" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_BDE527A3BA1583DD596D22114F4D1AE3_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_BDE527A3BA1583DD596D22114F4D1AE3" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_37F36C50189328138FA022114F4D0668" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_BDE527A3BA1583DD596D22114F4D1AE3" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EmbeddedDerivativeFinancialInstrumentsMember" xlink:label="loc_us-gaap_EmbeddedDerivativeFinancialInstrumentsMember_15B94359E9E6AFD483EC22114F4DD6B6" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_BDE527A3BA1583DD596D22114F4D1AE3" xlink:to="loc_us-gaap_EmbeddedDerivativeFinancialInstrumentsMember_15B94359E9E6AFD483EC22114F4DD6B6" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_UnobservableInputsUsedInDeterminingFairValueOfEmbeddedDerivativesAbstract" xlink:label="loc_afg_UnobservableInputsUsedInDeterminingFairValueOfEmbeddedDerivativesAbstract_2671C834CE9561268F0722114F4D2183" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueInputsLiabilitiesQuantitativeInformationLineItems_B9399D797A4DA12DBE8622114F4D15AC" xlink:to="loc_afg_UnobservableInputsUsedInDeterminingFairValueOfEmbeddedDerivativesAbstract_2671C834CE9561268F0722114F4D2183" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueInputsEntityCreditRisk" xlink:label="loc_us-gaap_FairValueInputsEntityCreditRisk_78E9C61084CBAD90BF9722114F4D9124" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_UnobservableInputsUsedInDeterminingFairValueOfEmbeddedDerivativesAbstract_2671C834CE9561268F0722114F4D2183" xlink:to="loc_us-gaap_FairValueInputsEntityCreditRisk_78E9C61084CBAD90BF9722114F4D9124" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FairValueInputsRiskMarginForUncertaintyInCashFlows" xlink:label="loc_afg_FairValueInputsRiskMarginForUncertaintyInCashFlows_DE527368E8134250172622114F4DB1A3" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_UnobservableInputsUsedInDeterminingFairValueOfEmbeddedDerivativesAbstract_2671C834CE9561268F0722114F4D2183" xlink:to="loc_afg_FairValueInputsRiskMarginForUncertaintyInCashFlows_DE527368E8134250172622114F4DB1A3" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FairValueInputsSurrenders" xlink:label="loc_afg_FairValueInputsSurrenders_72EC5C5FF3EC9565036222114F4DBCEF" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_UnobservableInputsUsedInDeterminingFairValueOfEmbeddedDerivativesAbstract_2671C834CE9561268F0722114F4D2183" xlink:to="loc_afg_FairValueInputsSurrenders_72EC5C5FF3EC9565036222114F4DBCEF" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FairValueInputsPartialSurrenders" xlink:label="loc_afg_FairValueInputsPartialSurrenders_782A9CFAC35295AED7AA22114F4DF279" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_UnobservableInputsUsedInDeterminingFairValueOfEmbeddedDerivativesAbstract_2671C834CE9561268F0722114F4D2183" xlink:to="loc_afg_FairValueInputsPartialSurrenders_782A9CFAC35295AED7AA22114F4DF279" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FairValueInputsAnnuitizations" xlink:label="loc_afg_FairValueInputsAnnuitizations_3E217BE57229C774779722114F4DE5B9" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_UnobservableInputsUsedInDeterminingFairValueOfEmbeddedDerivativesAbstract_2671C834CE9561268F0722114F4D2183" xlink:to="loc_afg_FairValueInputsAnnuitizations_3E217BE57229C774779722114F4DE5B9" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FairValueInputsDeaths" xlink:label="loc_afg_FairValueInputsDeaths_9004F72783BE5DD290DD22114F4D58F7" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_UnobservableInputsUsedInDeterminingFairValueOfEmbeddedDerivativesAbstract_2671C834CE9561268F0722114F4D2183" xlink:to="loc_afg_FairValueInputsDeaths_9004F72783BE5DD290DD22114F4D58F7" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FairValueInputsBudgetedOptionCosts" xlink:label="loc_afg_FairValueInputsBudgetedOptionCosts_8F59BA0F176A141650BB22114F4D4254" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_UnobservableInputsUsedInDeterminingFairValueOfEmbeddedDerivativesAbstract_2671C834CE9561268F0722114F4D2183" xlink:to="loc_afg_FairValueInputsBudgetedOptionCosts_8F59BA0F176A141650BB22114F4D4254" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/FairValueMeasurementsDetails2" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_2608221A295332487E5136E790B879CE" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_442D1E605C5DB2279B6C36E790B86925" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_2608221A295332487E5136E790B879CE" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_442D1E605C5DB2279B6C36E790B86925" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueByAssetClassAxis" xlink:label="loc_us-gaap_FairValueByAssetClassAxis_D73BC7238EFA5FE3721036E790B8DCA9" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable_442D1E605C5DB2279B6C36E790B86925" xlink:to="loc_us-gaap_FairValueByAssetClassAxis_D73BC7238EFA5FE3721036E790B8DCA9" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_F6068043B6433D144BDE36E790B89486_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_D73BC7238EFA5FE3721036E790B8DCA9" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_F6068043B6433D144BDE36E790B89486_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_F6068043B6433D144BDE36E790B89486" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_D73BC7238EFA5FE3721036E790B8DCA9" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_F6068043B6433D144BDE36E790B89486" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_USTreasuryAndGovernmentMember" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_4D29D421B9FFD42BF71636E790B809DC" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_F6068043B6433D144BDE36E790B89486" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_4D29D421B9FFD42BF71636E790B809DC" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_3F4D09353B94E5C6FEDC36E790B8B9A3" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_F6068043B6433D144BDE36E790B89486" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_3F4D09353B94E5C6FEDC36E790B8B9A3" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ResidentialMortgageBackedSecuritiesMember" xlink:label="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_61CB41F45E8B1BBF139B36E790B87F97" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_F6068043B6433D144BDE36E790B89486" xlink:to="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_61CB41F45E8B1BBF139B36E790B87F97" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CommercialMortgageBackedSecuritiesMember" xlink:label="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_8DE6D424A35D6B932FF636E790B88646" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_F6068043B6433D144BDE36E790B89486" xlink:to="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_8DE6D424A35D6B932FF636E790B88646" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AssetBackedSecuritiesMember" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_18602259B1FC00B8F4F436E790B8D321" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_F6068043B6433D144BDE36E790B89486" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_18602259B1FC00B8F4F436E790B8D321" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CorporateDebtSecuritiesMember" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_6A68C31B3DED5F137FC936E790B87BEB" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_F6068043B6433D144BDE36E790B89486" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_6A68C31B3DED5F137FC936E790B87BEB" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EquitySecuritiesMember" xlink:label="loc_us-gaap_EquitySecuritiesMember_52759C7F0FE885C507B436E790B8AA16" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_F6068043B6433D144BDE36E790B89486" xlink:to="loc_us-gaap_EquitySecuritiesMember_52759C7F0FE885C507B436E790B8AA16" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AssetsOfManagedInvestmentEntitiesMember" xlink:label="loc_afg_AssetsOfManagedInvestmentEntitiesMember_5BC57D7E2EE64FE37E4836E790B89067" xlink:type="locator" />
    <definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_F6068043B6433D144BDE36E790B89486" xlink:to="loc_afg_AssetsOfManagedInvestmentEntitiesMember_5BC57D7E2EE64FE37E4836E790B89067" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_9A3B5FCD6CB46F044BD336E790B80CDF" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_2608221A295332487E5136E790B879CE" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_9A3B5FCD6CB46F044BD336E790B80CDF" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_A272AB7EB0A80803205236E790B89950" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_2608221A295332487E5136E790B879CE" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_A272AB7EB0A80803205236E790B89950" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss_BBE2C6A053EDE275561436E790B81F92" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_2608221A295332487E5136E790B879CE" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss_BBE2C6A053EDE275561436E790B81F92" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_D0DE634D402D4F35A26B36E790B8A341" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_2608221A295332487E5136E790B879CE" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_D0DE634D402D4F35A26B36E790B8A341" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales_4BCDEE5C88172301CD4F36E790B8B370" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_2608221A295332487E5136E790B879CE" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales_4BCDEE5C88172301CD4F36E790B8B370" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3_F2DE75CE439E4C4ACE5036E790B8FB9E" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_2608221A295332487E5136E790B879CE" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3_F2DE75CE439E4C4ACE5036E790B8FB9E" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3_4082A0413B993F75487736E790B887AD" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_2608221A295332487E5136E790B879CE" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3_4082A0413B993F75487736E790B887AD" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/FairValueMeasurementsDetails3" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_B6CCF6AD82039BFE7A0D36E790A84872" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable_96C300571E0E45031A5A36E790A835D1" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_B6CCF6AD82039BFE7A0D36E790A84872" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable_96C300571E0E45031A5A36E790A835D1" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueByLiabilityClassAxis" xlink:label="loc_us-gaap_FairValueByLiabilityClassAxis_8B3150097ED44A539DCF36E790A8C700" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable_96C300571E0E45031A5A36E790A835D1" xlink:to="loc_us-gaap_FairValueByLiabilityClassAxis_8B3150097ED44A539DCF36E790A8C700" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_BE5BA3377B501C67881836E790A8CBDF_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByLiabilityClassAxis_8B3150097ED44A539DCF36E790A8C700" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_BE5BA3377B501C67881836E790A8CBDF_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_BE5BA3377B501C67881836E790A8CBDF" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByLiabilityClassAxis_8B3150097ED44A539DCF36E790A8C700" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_BE5BA3377B501C67881836E790A8CBDF" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_LiabilityOfManagedInvestmentEntitiesMember" xlink:label="loc_afg_LiabilityOfManagedInvestmentEntitiesMember_691D3F4813B100D9B3AA36E790A8BC6C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_BE5BA3377B501C67881836E790A8CBDF" xlink:to="loc_afg_LiabilityOfManagedInvestmentEntitiesMember_691D3F4813B100D9B3AA36E790A8BC6C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EmbeddedDerivativeFinancialInstrumentsMember" xlink:label="loc_us-gaap_EmbeddedDerivativeFinancialInstrumentsMember_0914BF7266F05DC4112836EF94C18365" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain_BE5BA3377B501C67881836E790A8CBDF" xlink:to="loc_us-gaap_EmbeddedDerivativeFinancialInstrumentsMember_0914BF7266F05DC4112836EF94C18365" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_C50050D423D52AB7489B36E790A80431" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_B6CCF6AD82039BFE7A0D36E790A84872" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_C50050D423D52AB7489B36E790A80431" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings_CEFA769FBE6CEB5C6CD136E790A81F29" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_B6CCF6AD82039BFE7A0D36E790A84872" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings_CEFA769FBE6CEB5C6CD136E790A81F29" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome_DAB863BC397DF4D2553836E790A85BA6" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_B6CCF6AD82039BFE7A0D36E790A84872" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome_DAB863BC397DF4D2553836E790A85BA6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues_9027AFA73A4A1895589936E790A8BD19" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_B6CCF6AD82039BFE7A0D36E790A84872" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityIssues_9027AFA73A4A1895589936E790A8BD19" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements_26E39AE88CF60CD713A436E790A8CF97" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_B6CCF6AD82039BFE7A0D36E790A84872" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements_26E39AE88CF60CD713A436E790A8CF97" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3_1BEA3843B4820B7F205936E790A82FCD" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_B6CCF6AD82039BFE7A0D36E790A84872" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3_1BEA3843B4820B7F205936E790A82FCD" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersOutOfLevel3" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersOutOfLevel3_FE0736AD13A98E96A8E236E790A843E4" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems_B6CCF6AD82039BFE7A0D36E790A84872" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersOutOfLevel3_FE0736AD13A98E96A8E236E790A843E4" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/FairValueMeasurementsDetails4" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems" xlink:label="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_45A1E1AB8279EBF2ACD0519AE00FC920" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueByBalanceSheetGroupingTable" xlink:label="loc_us-gaap_FairValueByBalanceSheetGroupingTable_616B9AD9C68C72D98154519AE00FB310" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_45A1E1AB8279EBF2ACD0519AE00FC920" xlink:to="loc_us-gaap_FairValueByBalanceSheetGroupingTable_616B9AD9C68C72D98154519AE00FB310" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueByMeasurementBasisAxis" xlink:label="loc_us-gaap_FairValueByMeasurementBasisAxis_34857134CE915A8D4179519AE00FFA72" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueByBalanceSheetGroupingTable_616B9AD9C68C72D98154519AE00FB310" xlink:to="loc_us-gaap_FairValueByMeasurementBasisAxis_34857134CE915A8D4179519AE00FFA72" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_CD1A2D3BD4FAC5BAB74951EB363600C9_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_34857134CE915A8D4179519AE00FFA72" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_CD1A2D3BD4FAC5BAB74951EB363600C9_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueDisclosureItemAmountsDomain" xlink:label="loc_us-gaap_FairValueDisclosureItemAmountsDomain_D80ECEAFE347B79E67CB519AE00FF408" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_34857134CE915A8D4179519AE00FFA72" xlink:to="loc_us-gaap_FairValueDisclosureItemAmountsDomain_D80ECEAFE347B79E67CB519AE00FF408" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_CD1A2D3BD4FAC5BAB74951EB363600C9" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_D80ECEAFE347B79E67CB519AE00FF408" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_CD1A2D3BD4FAC5BAB74951EB363600C9" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CarryingReportedAmountFairValueDisclosureMember" xlink:label="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_45D4C3CDDDC78252B51A519AE00F48DD" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_CD1A2D3BD4FAC5BAB74951EB363600C9" xlink:to="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_45D4C3CDDDC78252B51A519AE00F48DD" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember" xlink:label="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_354D59F2D1FF66D866D3519AE00FE653" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_CD1A2D3BD4FAC5BAB74951EB363600C9" xlink:to="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_354D59F2D1FF66D866D3519AE00FE653" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_092D841F7C4F2572DB3C519AE00F5324" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueByBalanceSheetGroupingTable_616B9AD9C68C72D98154519AE00FB310" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_092D841F7C4F2572DB3C519AE00F5324" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_DEB2E4855E6FF8C02D08519AE00F1A49_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_092D841F7C4F2572DB3C519AE00F5324" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_DEB2E4855E6FF8C02D08519AE00F1A49_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_DEB2E4855E6FF8C02D08519AE00F1A49" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_092D841F7C4F2572DB3C519AE00F5324" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_DEB2E4855E6FF8C02D08519AE00F1A49" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueInputsLevel1Member" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_576DCAAD6C3103C3DD2B519AE00FC8FE" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_DEB2E4855E6FF8C02D08519AE00F1A49" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_576DCAAD6C3103C3DD2B519AE00FC8FE" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueInputsLevel2Member" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_B43609E89CF754C7BAD1519AE00FEBBD" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_DEB2E4855E6FF8C02D08519AE00F1A49" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_B43609E89CF754C7BAD1519AE00FEBBD" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueInputsLevel3Member" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_9E8E3365F992CEFD1F39519AE00F6CF8" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_DEB2E4855E6FF8C02D08519AE00F1A49" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_9E8E3365F992CEFD1F39519AE00F6CF8" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FinancialInstrumentsFinancialAssetsAndLiabilitiesBalanceSheetGroupingsAbstract" xlink:label="loc_afg_FinancialInstrumentsFinancialAssetsAndLiabilitiesBalanceSheetGroupingsAbstract_3B5ACDF8E909A0264517519AE00FC3C9" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_45A1E1AB8279EBF2ACD0519AE00FC920" xlink:to="loc_afg_FinancialInstrumentsFinancialAssetsAndLiabilitiesBalanceSheetGroupingsAbstract_3B5ACDF8E909A0264517519AE00FC3C9" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract" xlink:label="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_4C0653CDB198E890D98F519AE00F7997" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_FinancialInstrumentsFinancialAssetsAndLiabilitiesBalanceSheetGroupingsAbstract_3B5ACDF8E909A0264517519AE00FC3C9" xlink:to="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_4C0653CDB198E890D98F519AE00F7997" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_0C351C5DC836FA72E5E9519AE00FD8C3" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_4C0653CDB198E890D98F519AE00F7997" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_0C351C5DC836FA72E5E9519AE00FD8C3" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MortgageLoansOnRealEstateCommercialAndConsumerNet" xlink:label="loc_us-gaap_MortgageLoansOnRealEstateCommercialAndConsumerNet_80EC282C031A900FDD26519AE00F79D1" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_4C0653CDB198E890D98F519AE00F7997" xlink:to="loc_us-gaap_MortgageLoansOnRealEstateCommercialAndConsumerNet_80EC282C031A900FDD26519AE00F79D1" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LoansInsurancePolicy" xlink:label="loc_us-gaap_LoansInsurancePolicy_2E691572218A26723C9A519AE00F5232" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_4C0653CDB198E890D98F519AE00F7997" xlink:to="loc_us-gaap_LoansInsurancePolicy_2E691572218A26723C9A519AE00F5232" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FinancialAssetsNotAccountedForAtFairValue" xlink:label="loc_afg_FinancialAssetsNotAccountedForAtFairValue_688159DA7B617B9E3A0D519AE00F7ECA" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_4C0653CDB198E890D98F519AE00F7997" xlink:to="loc_afg_FinancialAssetsNotAccountedForAtFairValue_688159DA7B617B9E3A0D519AE00F7ECA" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract" xlink:label="loc_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract_FAF4CC5B51ABCC09140E519AE00F98ED" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_FinancialInstrumentsFinancialAssetsAndLiabilitiesBalanceSheetGroupingsAbstract_3B5ACDF8E909A0264517519AE00FC3C9" xlink:to="loc_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract_FAF4CC5B51ABCC09140E519AE00F98ED" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AnnuityBenefitsAccumulatedExcludingLifeContingentAnnuities" xlink:label="loc_afg_AnnuityBenefitsAccumulatedExcludingLifeContingentAnnuities_C94EC127B579E1CEEE98519AE00FAA26" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract_FAF4CC5B51ABCC09140E519AE00F98ED" xlink:to="loc_afg_AnnuityBenefitsAccumulatedExcludingLifeContingentAnnuities_C94EC127B579E1CEEE98519AE00FAA26" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongTermDebt" xlink:label="loc_us-gaap_LongTermDebt_7AC42A30AF41624F5772519AE00F9897" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract_FAF4CC5B51ABCC09140E519AE00F98ED" xlink:to="loc_us-gaap_LongTermDebt_7AC42A30AF41624F5772519AE00F9897" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FinancialLiabilitiesNotAccountedForAtFairValue" xlink:label="loc_afg_FinancialLiabilitiesNotAccountedForAtFairValue_6AEDA759348036A60EA3519AE00F4F47" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract_FAF4CC5B51ABCC09140E519AE00F98ED" xlink:to="loc_afg_FinancialLiabilitiesNotAccountedForAtFairValue_6AEDA759348036A60EA3519AE00F4F47" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/FairValueMeasurementsDetailsTextual" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_650DE8141F9D9FEAA827855BB6EA4005" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_8746EC9094FECC4B8A4C855BB6E81D29" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_650DE8141F9D9FEAA827855BB6EA4005" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_8746EC9094FECC4B8A4C855BB6E81D29" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaap_StatementClassOfStockAxis_17F4E1628986E1D3D320855BB6E90087" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_8746EC9094FECC4B8A4C855BB6E81D29" xlink:to="loc_us-gaap_StatementClassOfStockAxis_17F4E1628986E1D3D320855BB6E90087" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaap_ClassOfStockDomain_CEA926B58713A3D4AEA3855BB6E9C175_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_17F4E1628986E1D3D320855BB6E90087" xlink:to="loc_us-gaap_ClassOfStockDomain_CEA926B58713A3D4AEA3855BB6E9C175_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaap_ClassOfStockDomain_CEA926B58713A3D4AEA3855BB6E9C175" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_17F4E1628986E1D3D320855BB6E90087" xlink:to="loc_us-gaap_ClassOfStockDomain_CEA926B58713A3D4AEA3855BB6E9C175" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PreferredStockMember" xlink:label="loc_us-gaap_PreferredStockMember_35D91B5BA48D12ED3589855BB6E9310A" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_CEA926B58713A3D4AEA3855BB6E9C175" xlink:to="loc_us-gaap_PreferredStockMember_35D91B5BA48D12ED3589855BB6E9310A" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember_22F10357AC01B6D89C30855BB6E96A9C" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_CEA926B58713A3D4AEA3855BB6E9C175" xlink:to="loc_us-gaap_CommonStockMember_22F10357AC01B6D89C30855BB6E96A9C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RedeemablePreferredStockMember" xlink:label="loc_us-gaap_RedeemablePreferredStockMember_BA8E2CCD914763537E60855BB6E9C9B5" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_CEA926B58713A3D4AEA3855BB6E9C175" xlink:to="loc_us-gaap_RedeemablePreferredStockMember_BA8E2CCD914763537E60855BB6E9C9B5" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_BD2C5B47C82A096A204A855BB6E9D67B" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_8746EC9094FECC4B8A4C855BB6E81D29" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_BD2C5B47C82A096A204A855BB6E9D67B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_91CDF9F675A374405F83855BB6E9E188_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_BD2C5B47C82A096A204A855BB6E9D67B" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_91CDF9F675A374405F83855BB6E9E188_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_91CDF9F675A374405F83855BB6E9E188" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_BD2C5B47C82A096A204A855BB6E9D67B" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_91CDF9F675A374405F83855BB6E9E188" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FixedIndexedAnnuitiesEmbeddedDerivativeMember" xlink:label="loc_afg_FixedIndexedAnnuitiesEmbeddedDerivativeMember_8B8E2F4671CBBD93A1CC855BB6E96C0C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_91CDF9F675A374405F83855BB6E9E188" xlink:to="loc_afg_FixedIndexedAnnuitiesEmbeddedDerivativeMember_8B8E2F4671CBBD93A1CC855BB6E96C0C" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FixedIndexedAnnuitiesEmbeddedDerivativeMajorityofFutureYearsMember" xlink:label="loc_afg_FixedIndexedAnnuitiesEmbeddedDerivativeMajorityofFutureYearsMember_5C90B60775DBF3E3E95A855BB6E93338" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_91CDF9F675A374405F83855BB6E9E188" xlink:to="loc_afg_FixedIndexedAnnuitiesEmbeddedDerivativeMajorityofFutureYearsMember_5C90B60775DBF3E3E95A855BB6E93338" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_B55CFC3A2941CBE36105855BB6E979BD" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_8746EC9094FECC4B8A4C855BB6E81D29" xlink:to="loc_us-gaap_RangeAxis_B55CFC3A2941CBE36105855BB6E979BD" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_9037E3F764E547FAB724855BB6E9015F_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_B55CFC3A2941CBE36105855BB6E979BD" xlink:to="loc_us-gaap_RangeMember_9037E3F764E547FAB724855BB6E9015F_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_9037E3F764E547FAB724855BB6E9015F" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_B55CFC3A2941CBE36105855BB6E979BD" xlink:to="loc_us-gaap_RangeMember_9037E3F764E547FAB724855BB6E9015F" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_ED5178334355D2CB77E2855BB6E93096" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_9037E3F764E547FAB724855BB6E9015F" xlink:to="loc_us-gaap_MinimumMember_ED5178334355D2CB77E2855BB6E93096" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_4133225BB9AD2808551C855BB6E9E372" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_9037E3F764E547FAB724855BB6E9015F" xlink:to="loc_us-gaap_MaximumMember_4133225BB9AD2808551C855BB6E9E372" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FairValueMeasurementsTextualAbstract" xlink:label="loc_afg_FairValueMeasurementsTextualAbstract_61D986024A1EF78F6F64855BB6EAB15C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_650DE8141F9D9FEAA827855BB6EA4005" xlink:to="loc_afg_FairValueMeasurementsTextualAbstract_61D986024A1EF78F6F64855BB6EAB15C" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_NumberOfInternalInvestmentProfessionals" xlink:label="loc_afg_NumberOfInternalInvestmentProfessionals_B45CEFD066691CBCF819855BB6EA7CC1" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_FairValueMeasurementsTextualAbstract_61D986024A1EF78F6F64855BB6EAB15C" xlink:to="loc_afg_NumberOfInternalInvestmentProfessionals_B45CEFD066691CBCF819855BB6EA7CC1" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_NumberofStocksTransferredfromLevel1toLevel2DuringthePeriod" xlink:label="loc_afg_NumberofStocksTransferredfromLevel1toLevel2DuringthePeriod_D92DB76D540E961C3F4C855BB6EA4BA1" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_FairValueMeasurementsTextualAbstract_61D986024A1EF78F6F64855BB6EAB15C" xlink:to="loc_afg_NumberofStocksTransferredfromLevel1toLevel2DuringthePeriod_D92DB76D540E961C3F4C855BB6EA4BA1" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_NumberofStocksTransferredfromLevel2toLevel1DuringthePeriod" xlink:label="loc_afg_NumberofStocksTransferredfromLevel2toLevel1DuringthePeriod_4604393DB01100508E18855BB6EA267B" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_FairValueMeasurementsTextualAbstract_61D986024A1EF78F6F64855BB6EAB15C" xlink:to="loc_afg_NumberofStocksTransferredfromLevel2toLevel1DuringthePeriod_4604393DB01100508E18855BB6EA267B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueAssetsLevel1ToLevel2TransfersAmount" xlink:label="loc_us-gaap_FairValueAssetsLevel1ToLevel2TransfersAmount_C64BDC7F502F14E48DCF855BB6EACC63" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_FairValueMeasurementsTextualAbstract_61D986024A1EF78F6F64855BB6EAB15C" xlink:to="loc_us-gaap_FairValueAssetsLevel1ToLevel2TransfersAmount_C64BDC7F502F14E48DCF855BB6EACC63" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FairValueAssetsLevel2toLevel1TransfersDuringthePeriodAmount" xlink:label="loc_afg_FairValueAssetsLevel2toLevel1TransfersDuringthePeriodAmount_40F0D94CE669E6BDB4D4855BB6EAE023" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_FairValueMeasurementsTextualAbstract_61D986024A1EF78F6F64855BB6EAB15C" xlink:to="loc_afg_FairValueAssetsLevel2toLevel1TransfersDuringthePeriodAmount_40F0D94CE669E6BDB4D4855BB6EAE023" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FairValueAssetsLevel2ToLevel1TransfersAmount" xlink:label="loc_us-gaap_FairValueAssetsLevel2ToLevel1TransfersAmount_9A0EED9B55935BD5B77D855BB6EA65F5" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_FairValueMeasurementsTextualAbstract_61D986024A1EF78F6F64855BB6EAB15C" xlink:to="loc_us-gaap_FairValueAssetsLevel2ToLevel1TransfersAmount_9A0EED9B55935BD5B77D855BB6EA65F5" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_LevelThreeAssetAsPercentageOfAssetMeasuredAtFairValue" xlink:label="loc_afg_LevelThreeAssetAsPercentageOfAssetMeasuredAtFairValue_EDD64419A8CB71A4636A855BB6EA5CF8" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_FairValueMeasurementsTextualAbstract_61D986024A1EF78F6F64855BB6EAB15C" xlink:to="loc_afg_LevelThreeAssetAsPercentageOfAssetMeasuredAtFairValue_EDD64419A8CB71A4636A855BB6EA5CF8" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_PercentageOfLevelThreeAssetsThatWerePricedUsingNonBindingBrokerQuotes" xlink:label="loc_afg_PercentageOfLevelThreeAssetsThatWerePricedUsingNonBindingBrokerQuotes_28183EFDE0ED55E2552C855BB6EA4C5A" xlink:type="locator" />
    <definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_FairValueMeasurementsTextualAbstract_61D986024A1EF78F6F64855BB6EAB15C" xlink:to="loc_afg_PercentageOfLevelThreeAssetsThatWerePricedUsingNonBindingBrokerQuotes_28183EFDE0ED55E2552C855BB6EA4C5A" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_LevelThreeAssetsThatWerePricedUsingNonBindingBrokerQuotes" xlink:label="loc_afg_LevelThreeAssetsThatWerePricedUsingNonBindingBrokerQuotes_A8A66E0B08E25254D3CB855BB6EA65C6" xlink:type="locator" />
    <definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_FairValueMeasurementsTextualAbstract_61D986024A1EF78F6F64855BB6EAB15C" xlink:to="loc_afg_LevelThreeAssetsThatWerePricedUsingNonBindingBrokerQuotes_A8A66E0B08E25254D3CB855BB6EA65C6" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_PercentageOfInternallyDevelopedLevelThreeAssetsToTotalAssets" xlink:label="loc_afg_PercentageOfInternallyDevelopedLevelThreeAssetsToTotalAssets_5237949B2DB7C76BB5F8855BB6EA7685" xlink:type="locator" />
    <definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_FairValueMeasurementsTextualAbstract_61D986024A1EF78F6F64855BB6EAB15C" xlink:to="loc_afg_PercentageOfInternallyDevelopedLevelThreeAssetsToTotalAssets_5237949B2DB7C76BB5F8855BB6EA7685" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_PercentageOfInternallyDevelopedLevelThreeAssetsToShareholdersEquity" xlink:label="loc_afg_PercentageOfInternallyDevelopedLevelThreeAssetsToShareholdersEquity_A45FB30F1658ECF9A9AC855BB6EAB591" xlink:type="locator" />
    <definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_FairValueMeasurementsTextualAbstract_61D986024A1EF78F6F64855BB6EAB15C" xlink:to="loc_afg_PercentageOfInternallyDevelopedLevelThreeAssetsToShareholdersEquity_A45FB30F1658ECF9A9AC855BB6EAB591" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DerivativeLiabilities" xlink:label="loc_us-gaap_DerivativeLiabilities_D06BAFBDB014B5FEE197855BB6EA6BDF" xlink:type="locator" />
    <definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_FairValueMeasurementsTextualAbstract_61D986024A1EF78F6F64855BB6EAB15C" xlink:to="loc_us-gaap_DerivativeLiabilities_D06BAFBDB014B5FEE197855BB6EA6BDF" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FairValueInputsSurrenders" xlink:label="loc_afg_FairValueInputsSurrenders_A287A5365E539A1741C6855BB6EA7214" xlink:type="locator" />
    <definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_FairValueMeasurementsTextualAbstract_61D986024A1EF78F6F64855BB6EAB15C" xlink:to="loc_afg_FairValueInputsSurrenders_A287A5365E539A1741C6855BB6EA7214" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarningsOnLiabilitiesStillOutstanding" xlink:label="loc_afg_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarningsOnLiabilitiesStillOutstanding_3DD74E8C0B06B9D238BD855BB6EA2378" xlink:type="locator" />
    <definitionArc order="14" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_FairValueMeasurementsTextualAbstract_61D986024A1EF78F6F64855BB6EAB15C" xlink:to="loc_afg_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarningsOnLiabilitiesStillOutstanding_3DD74E8C0B06B9D238BD855BB6EA2378" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/FairValueMeasurementsTables" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/GoodwillAndOtherIntangibles" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/GoodwillAndOtherIntangiblesDetailsTextual" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/IncomeTaxes" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/IncomeTaxesDetails" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/IncomeTaxesDetailsTextual" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/IncomeTaxesTables" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/Investments" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/InvestmentsDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_4CD8CABDCE9622AAD47CAD4A480938EA" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesTable" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_2DFC89F0FE016B79FDD7AD4A4809B48C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_4CD8CABDCE9622AAD47CAD4A480938EA" xlink:to="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_2DFC89F0FE016B79FDD7AD4A4809B48C" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_13B24B93C1ED6336468CAD4A4809145C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_2DFC89F0FE016B79FDD7AD4A4809B48C" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_13B24B93C1ED6336468CAD4A4809145C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_BAFA36F62A57115658E7AD4A480908FB_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_13B24B93C1ED6336468CAD4A4809145C" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_BAFA36F62A57115658E7AD4A480908FB_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_BAFA36F62A57115658E7AD4A480908FB" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_13B24B93C1ED6336468CAD4A4809145C" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_BAFA36F62A57115658E7AD4A480908FB" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_USTreasuryAndGovernmentMember" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_EBE7AD20FF76EACA13DCAD4A48093E80" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_BAFA36F62A57115658E7AD4A480908FB" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_EBE7AD20FF76EACA13DCAD4A48093E80" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_20B06C0AD0FD16CB2D74AD4A4809660D" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_BAFA36F62A57115658E7AD4A480908FB" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_20B06C0AD0FD16CB2D74AD4A4809660D" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember" xlink:label="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_12243A75EEA44812AF47AD4A4809E45F" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_BAFA36F62A57115658E7AD4A480908FB" xlink:to="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_12243A75EEA44812AF47AD4A4809E45F" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ResidentialMortgageBackedSecuritiesMember" xlink:label="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_9F6515A73D7D01E043B3AD4A48098A6D" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_BAFA36F62A57115658E7AD4A480908FB" xlink:to="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_9F6515A73D7D01E043B3AD4A48098A6D" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CommercialMortgageBackedSecuritiesMember" xlink:label="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_0E552BC926FBD7FF3184AD4A48094676" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_BAFA36F62A57115658E7AD4A480908FB" xlink:to="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_0E552BC926FBD7FF3184AD4A48094676" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AssetBackedSecuritiesMember" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_40A8770BB8978178AF69AD4A480931E6" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_BAFA36F62A57115658E7AD4A480908FB" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_40A8770BB8978178AF69AD4A480931E6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CorporateDebtSecuritiesMember" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_065D14CCA5FA0A3DB384AD4A4809DC1B" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_BAFA36F62A57115658E7AD4A480908FB" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_065D14CCA5FA0A3DB384AD4A4809DC1B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FixedMaturitiesMember" xlink:label="loc_us-gaap_FixedMaturitiesMember_80C8D185DD3088BE0CB5AD4A4809BCA1" xlink:type="locator" />
    <definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_BAFA36F62A57115658E7AD4A480908FB" xlink:to="loc_us-gaap_FixedMaturitiesMember_80C8D185DD3088BE0CB5AD4A4809BCA1" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember_DC63FDBB9FB983FBF3DEAD4A4809F673" xlink:type="locator" />
    <definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_BAFA36F62A57115658E7AD4A480908FB" xlink:to="loc_us-gaap_CommonStockMember_DC63FDBB9FB983FBF3DEAD4A4809F673" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PreferredStockMember" xlink:label="loc_us-gaap_PreferredStockMember_F59897EA5563064CB5C0AD4A4809A5BE" xlink:type="locator" />
    <definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_BAFA36F62A57115658E7AD4A480908FB" xlink:to="loc_us-gaap_PreferredStockMember_F59897EA5563064CB5C0AD4A4809A5BE" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AvailableForSaleFixedMaturitiesAndEquitySecuritiesAbstract" xlink:label="loc_afg_AvailableForSaleFixedMaturitiesAndEquitySecuritiesAbstract_54843668A72C90F16EBCAD4A4809FC2D" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_4CD8CABDCE9622AAD47CAD4A480938EA" xlink:to="loc_afg_AvailableForSaleFixedMaturitiesAndEquitySecuritiesAbstract_54843668A72C90F16EBCAD4A4809FC2D" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesAmortizedCost" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesAmortizedCost_C3E9D9F8B001AFA7C010AD4A48095A5C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_AvailableForSaleFixedMaturitiesAndEquitySecuritiesAbstract_54843668A72C90F16EBCAD4A4809FC2D" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesAmortizedCost_C3E9D9F8B001AFA7C010AD4A48095A5C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecurities" xlink:label="loc_us-gaap_AvailableForSaleSecurities_BB3965F46875F62AD9F3AD4A480938BA" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_AvailableForSaleFixedMaturitiesAndEquitySecuritiesAbstract_54843668A72C90F16EBCAD4A4809FC2D" xlink:to="loc_us-gaap_AvailableForSaleSecurities_BB3965F46875F62AD9F3AD4A480938BA" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_3D2F82C528DE4A320087AD4A48090AA1" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_AvailableForSaleFixedMaturitiesAndEquitySecuritiesAbstract_54843668A72C90F16EBCAD4A4809FC2D" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_3D2F82C528DE4A320087AD4A48090AA1" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_8A165101CDC2CA1206F7AD4A4809C90B" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_AvailableForSaleFixedMaturitiesAndEquitySecuritiesAbstract_54843668A72C90F16EBCAD4A4809FC2D" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_8A165101CDC2CA1206F7AD4A4809C90B" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/InvestmentsDetails1" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_3DEB18E0955BB0155D7D41D5658A1984" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesTable" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_A331E3973706819D5CF441D56589C8F4" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_3DEB18E0955BB0155D7D41D5658A1984" xlink:to="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_A331E3973706819D5CF441D56589C8F4" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_DE67A1A8FC61D7079C2041D56589CD19" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_A331E3973706819D5CF441D56589C8F4" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_DE67A1A8FC61D7079C2041D56589CD19" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_63F43ECD10411877A36441D56589BC58_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_DE67A1A8FC61D7079C2041D56589CD19" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_63F43ECD10411877A36441D56589BC58_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_63F43ECD10411877A36441D56589BC58" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_DE67A1A8FC61D7079C2041D56589CD19" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_63F43ECD10411877A36441D56589BC58" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_USTreasuryAndGovernmentMember" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_8D29C102167FCC03684341D56589FAA2" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_63F43ECD10411877A36441D56589BC58" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_8D29C102167FCC03684341D56589FAA2" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_E53949A8B0BD267CAA0041D56589A1F9" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_63F43ECD10411877A36441D56589BC58" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_E53949A8B0BD267CAA0041D56589A1F9" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember" xlink:label="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_0B464293F43B3AE35C4041D565893464" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_63F43ECD10411877A36441D56589BC58" xlink:to="loc_us-gaap_ForeignGovernmentDebtSecuritiesMember_0B464293F43B3AE35C4041D565893464" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ResidentialMortgageBackedSecuritiesMember" xlink:label="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_FBB317F797304F0E047E41D565897EBB" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_63F43ECD10411877A36441D56589BC58" xlink:to="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_FBB317F797304F0E047E41D565897EBB" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CommercialMortgageBackedSecuritiesMember" xlink:label="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_556125936FAC45D0450E41D565897171" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_63F43ECD10411877A36441D56589BC58" xlink:to="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_556125936FAC45D0450E41D565897171" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AssetBackedSecuritiesMember" xlink:label="loc_us-gaap_AssetBackedSecuritiesMember_DDBE8CCE415B65BC214541D56589C38E" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_63F43ECD10411877A36441D56589BC58" xlink:to="loc_us-gaap_AssetBackedSecuritiesMember_DDBE8CCE415B65BC214541D56589C38E" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CorporateDebtSecuritiesMember" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember_E6A4AF13F5BDCFC5486642820EB69216" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_63F43ECD10411877A36441D56589BC58" xlink:to="loc_us-gaap_CorporateDebtSecuritiesMember_E6A4AF13F5BDCFC5486642820EB69216" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FixedMaturitiesMember" xlink:label="loc_us-gaap_FixedMaturitiesMember_47E813318C04CA92EDB041D5658A8682" xlink:type="locator" />
    <definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_63F43ECD10411877A36441D56589BC58" xlink:to="loc_us-gaap_FixedMaturitiesMember_47E813318C04CA92EDB041D5658A8682" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember_A9E077ECE112AB126AEC41D5658A03F4" xlink:type="locator" />
    <definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_63F43ECD10411877A36441D56589BC58" xlink:to="loc_us-gaap_CommonStockMember_A9E077ECE112AB126AEC41D5658A03F4" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PreferredStockMember" xlink:label="loc_us-gaap_PreferredStockMember_B0D6D99577C865460D4B41D5658A0CCB" xlink:type="locator" />
    <definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_63F43ECD10411877A36441D56589BC58" xlink:to="loc_us-gaap_PreferredStockMember_B0D6D99577C865460D4B41D5658A0CCB" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract_33396F193F8E72B0668041D5658AB846" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_3DEB18E0955BB0155D7D41D5658A1984" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract_33396F193F8E72B0668041D5658AB846" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_2E24E57D41BF294CA45C41D5658A4BC3" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract_33396F193F8E72B0668041D5658AB846" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_2E24E57D41BF294CA45C41D5658A4BC3" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue_780928B2DCD1A03CA6E641D5658AD0CC" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract_33396F193F8E72B0668041D5658AB846" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue_780928B2DCD1A03CA6E641D5658AD0CC" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValueAsPercentageOfCost" xlink:label="loc_afg_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValueAsPercentageOfCost_07309A8FA4EBDAF3699641D5658AB2CF" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract_33396F193F8E72B0668041D5658AB846" xlink:to="loc_afg_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValueAsPercentageOfCost_07309A8FA4EBDAF3699641D5658AB2CF" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_856B399BDCFDFCFA642841D5658AA318" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract_33396F193F8E72B0668041D5658AB846" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_856B399BDCFDFCFA642841D5658AA318" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue_FD77EB43095F37A449D841D5658AB37A" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract_33396F193F8E72B0668041D5658AB846" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue_FD77EB43095F37A449D841D5658AB37A" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValueAsPercentageOfCost" xlink:label="loc_afg_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValueAsPercentageOfCost_9872A7CCDAFA82ABB76841D5658AAFFF" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAbstract_33396F193F8E72B0668041D5658AB846" xlink:to="loc_afg_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValueAsPercentageOfCost_9872A7CCDAFA82ABB76841D5658AAFFF" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/InvestmentsDetails2" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/InvestmentsDetails3" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_7D056FC9BC122D7F8FD622114EAD81DC" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesTable" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_CC924BA11CD78858707922114EACBF46" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_7D056FC9BC122D7F8FD622114EAD81DC" xlink:to="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_CC924BA11CD78858707922114EACBF46" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_B2B62C06344C2D6F69FA22114EACAC98" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_CC924BA11CD78858707922114EACBF46" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_B2B62C06344C2D6F69FA22114EACAC98" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_30806FF4DB92ACF582A722114EAC3C3A_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_B2B62C06344C2D6F69FA22114EACAC98" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_30806FF4DB92ACF582A722114EAC3C3A_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_30806FF4DB92ACF582A722114EAC3C3A" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_B2B62C06344C2D6F69FA22114EACAC98" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_30806FF4DB92ACF582A722114EAC3C3A" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FixedMaturitiesMember" xlink:label="loc_us-gaap_FixedMaturitiesMember_B36B65F464ABC3B57E1D22114EAD38AA" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_30806FF4DB92ACF582A722114EAC3C3A" xlink:to="loc_us-gaap_FixedMaturitiesMember_B36B65F464ABC3B57E1D22114EAD38AA" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_7D056FC9BC122D7F8FD622114EAD81DC" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_935425090FC77F71950222114EAD1E9E" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_935425090FC77F71950222114EAD1E9E" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_5483C32C2484013C93A422114EAD677A" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_5483C32C2484013C93A422114EAD677A" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValuePercent" xlink:label="loc_afg_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValuePercent_B5FC08DA77C66639144422114EADB835" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_afg_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValuePercent_B5FC08DA77C66639144422114EADB835" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost_44B0FD22C9E816347F4E22114EAD4B51" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost_44B0FD22C9E816347F4E22114EAD4B51" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_10CB7E274286F01BCF5922114EAD8C86" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_10CB7E274286F01BCF5922114EAD8C86" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValuePercent" xlink:label="loc_afg_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValuePercent_05691319F552D85B84CF22114EADB43C" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_afg_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValuePercent_05691319F552D85B84CF22114EADB43C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost_A4FE3FABC939AB6A992222114EAD39A1" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost_A4FE3FABC939AB6A992222114EAD39A1" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_35DE2AB19D15536A98CE22114EADD1D8" xlink:type="locator" />
    <definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_35DE2AB19D15536A98CE22114EADD1D8" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValuePercent" xlink:label="loc_afg_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValuePercent_C57AEA3DBDEC34A03C5722114EAD672F" xlink:type="locator" />
    <definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_afg_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValuePercent_C57AEA3DBDEC34A03C5722114EAD672F" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost_4E1F61CCCE5DFB75B3B322114EADA394" xlink:type="locator" />
    <definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost_4E1F61CCCE5DFB75B3B322114EADA394" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue_9727F898660BCD93539622114EAD4585" xlink:type="locator" />
    <definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue_9727F898660BCD93539622114EAD4585" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValuePercent" xlink:label="loc_afg_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValuePercent_A57CA907F1DAA457F94322114EADBC7C" xlink:type="locator" />
    <definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_afg_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValuePercent_A57CA907F1DAA457F94322114EADBC7C" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AvailableForSaleSecuritiesDebtMaturitiesExcludingAbsAndMbsAmortizedCost" xlink:label="loc_afg_AvailableForSaleSecuritiesDebtMaturitiesExcludingAbsAndMbsAmortizedCost_668DC1CAB37B5D0C674022114EAD13E7" xlink:type="locator" />
    <definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_afg_AvailableForSaleSecuritiesDebtMaturitiesExcludingAbsAndMbsAmortizedCost_668DC1CAB37B5D0C674022114EAD13E7" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AvailableForSaleSecuritiesDebtMaturitiesExcludingAbsAndMbsFairValue" xlink:label="loc_afg_AvailableForSaleSecuritiesDebtMaturitiesExcludingAbsAndMbsFairValue_1168D65EA9B77B9B75CD22114EAE7159" xlink:type="locator" />
    <definitionArc order="14" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_afg_AvailableForSaleSecuritiesDebtMaturitiesExcludingAbsAndMbsFairValue_1168D65EA9B77B9B75CD22114EAE7159" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AvailableForSaleSecuritiesDebtMaturitiesExcludingAbsAndMbsFairValuePercent" xlink:label="loc_afg_AvailableForSaleSecuritiesDebtMaturitiesExcludingAbsAndMbsFairValuePercent_0361C167B560483E4BE322114EAED66B" xlink:type="locator" />
    <definitionArc order="15" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_afg_AvailableForSaleSecuritiesDebtMaturitiesExcludingAbsAndMbsFairValuePercent_0361C167B560483E4BE322114EAED66B" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AvailableForSaleSecuritiesAbsAmortizedCost" xlink:label="loc_afg_AvailableForSaleSecuritiesAbsAmortizedCost_8CB7AFA885D1005E121022114EAE4C6E" xlink:type="locator" />
    <definitionArc order="16" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_afg_AvailableForSaleSecuritiesAbsAmortizedCost_8CB7AFA885D1005E121022114EAE4C6E" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AvailableForSaleSecuritiesAbsFairValue" xlink:label="loc_afg_AvailableForSaleSecuritiesAbsFairValue_30656177771D870B6B3F22114EAEDC1D" xlink:type="locator" />
    <definitionArc order="17" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_afg_AvailableForSaleSecuritiesAbsFairValue_30656177771D870B6B3F22114EAEDC1D" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AvailableForSaleSecuritiesAbsFairValuePercent" xlink:label="loc_afg_AvailableForSaleSecuritiesAbsFairValuePercent_A220403F8C41E353B43222114EAEEB27" xlink:type="locator" />
    <definitionArc order="18" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_afg_AvailableForSaleSecuritiesAbsFairValuePercent_A220403F8C41E353B43222114EAEEB27" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AvailableForSaleSecuritiesMbsAmortizedCost" xlink:label="loc_afg_AvailableForSaleSecuritiesMbsAmortizedCost_B4FB9E4531E4A1497CB422114EAEDC5B" xlink:type="locator" />
    <definitionArc order="19" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_afg_AvailableForSaleSecuritiesMbsAmortizedCost_B4FB9E4531E4A1497CB422114EAEDC5B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MortgageBackedSecuritiesAvailableForSaleFairValueDisclosure" xlink:label="loc_us-gaap_MortgageBackedSecuritiesAvailableForSaleFairValueDisclosure_0D0B4B288D4B73A74E8522114EAED566" xlink:type="locator" />
    <definitionArc order="20" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_us-gaap_MortgageBackedSecuritiesAvailableForSaleFairValueDisclosure_0D0B4B288D4B73A74E8522114EAED566" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AvailableForSaleSecuritiesMbsFairValuePercent" xlink:label="loc_afg_AvailableForSaleSecuritiesMbsFairValuePercent_BB4530ADAA8C4C1A25EF22114EAE9BD6" xlink:type="locator" />
    <definitionArc order="21" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_afg_AvailableForSaleSecuritiesMbsFairValuePercent_BB4530ADAA8C4C1A25EF22114EAE9BD6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesAmortizedCost" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesAmortizedCost_3FC97258A5414E5072C522114EAEB609" xlink:type="locator" />
    <definitionArc order="22" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesAmortizedCost_3FC97258A5414E5072C522114EAEB609" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecurities" xlink:label="loc_us-gaap_AvailableForSaleSecurities_6C1F326FAB1A6DBE3BFB22114EAEA223" xlink:type="locator" />
    <definitionArc order="23" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_us-gaap_AvailableForSaleSecurities_6C1F326FAB1A6DBE3BFB22114EAEA223" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AvailableForSaleSecuritiesDebtMaturitiesFairValuePercent" xlink:label="loc_afg_AvailableForSaleSecuritiesDebtMaturitiesFairValuePercent_25406C2B7376FE3F821A22114EAEF24B" xlink:type="locator" />
    <definitionArc order="24" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_D4E952EA039BAD2AB10B22114EAD01CD" xlink:to="loc_afg_AvailableForSaleSecuritiesDebtMaturitiesFairValuePercent_25406C2B7376FE3F821A22114EAEF24B" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/InvestmentsDetails4" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_EC0CA64FAA0ED2C6B2A122114FD7690F" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesTable" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_0B7D562D65503AB8B33F22114FD67C58" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_EC0CA64FAA0ED2C6B2A122114FD7690F" xlink:to="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_0B7D562D65503AB8B33F22114FD67C58" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_D6F3D68E453B1A761EDD22114FD6619E" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_0B7D562D65503AB8B33F22114FD67C58" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_D6F3D68E453B1A761EDD22114FD6619E" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_DBD5F2581BB37916093722114FD603A5_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_D6F3D68E453B1A761EDD22114FD6619E" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_DBD5F2581BB37916093722114FD603A5_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_DBD5F2581BB37916093722114FD603A5" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_D6F3D68E453B1A761EDD22114FD6619E" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_DBD5F2581BB37916093722114FD603A5" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FixedMaturitiesAnnuitySegmentMember" xlink:label="loc_afg_FixedMaturitiesAnnuitySegmentMember_06F8CBAD86D54D83D1F922114FD67D4C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_DBD5F2581BB37916093722114FD603A5" xlink:to="loc_afg_FixedMaturitiesAnnuitySegmentMember_06F8CBAD86D54D83D1F922114FD67D4C" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FixedMaturitiesAllOtherSegmentsMember" xlink:label="loc_afg_FixedMaturitiesAllOtherSegmentsMember_2203D8021EFC912B701C22114FD6D93D" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_DBD5F2581BB37916093722114FD603A5" xlink:to="loc_afg_FixedMaturitiesAllOtherSegmentsMember_2203D8021EFC912B701C22114FD6D93D" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EquitySecuritiesMember" xlink:label="loc_us-gaap_EquitySecuritiesMember_E4CA0048168DE248484622114FD6B9CC" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_DBD5F2581BB37916093722114FD603A5" xlink:to="loc_us-gaap_EquitySecuritiesMember_E4CA0048168DE248484622114FD6B9CC" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_DeferredPolicyAcquisitionCostsAnnuitySegmentMember" xlink:label="loc_afg_DeferredPolicyAcquisitionCostsAnnuitySegmentMember_D06B5E6C237A8B4BEA8A22114FD6EE6A" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_DBD5F2581BB37916093722114FD603A5" xlink:to="loc_afg_DeferredPolicyAcquisitionCostsAnnuitySegmentMember_D06B5E6C237A8B4BEA8A22114FD6EE6A" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AnnuityBenefitsAndOtherLiabilitiesMember" xlink:label="loc_afg_AnnuityBenefitsAndOtherLiabilitiesMember_6A1F41F866ACA773224422114FD6D137" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_DBD5F2581BB37916093722114FD603A5" xlink:to="loc_afg_AnnuityBenefitsAndOtherLiabilitiesMember_6A1F41F866ACA773224422114FD6D137" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_LifeAccidentAndHealthReservesMember" xlink:label="loc_afg_LifeAccidentAndHealthReservesMember_F08C8F761694622C103322114FD72528" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_DBD5F2581BB37916093722114FD603A5" xlink:to="loc_afg_LifeAccidentAndHealthReservesMember_F08C8F761694622C103322114FD72528" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_UnearnedRevenueMember" xlink:label="loc_afg_UnearnedRevenueMember_98F784C15F99E96525C622114FD760F8" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_DBD5F2581BB37916093722114FD603A5" xlink:to="loc_afg_UnearnedRevenueMember_98F784C15F99E96525C622114FD760F8" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_ComponentsOfNetUnrealizedGainOnSecuritiesIncludedInAccumulatedOtherComprehensiveIncomeAbstract" xlink:label="loc_afg_ComponentsOfNetUnrealizedGainOnSecuritiesIncludedInAccumulatedOtherComprehensiveIncomeAbstract_910377BB99638F4A3CFD22114FD7452A" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_EC0CA64FAA0ED2C6B2A122114FD7690F" xlink:to="loc_afg_ComponentsOfNetUnrealizedGainOnSecuritiesIncludedInAccumulatedOtherComprehensiveIncomeAbstract_910377BB99638F4A3CFD22114FD7452A" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_UnrealizedGainOnSecuritiesIncludedInAccumulatedOtherComprehensiveIncomeAbstract" xlink:label="loc_afg_UnrealizedGainOnSecuritiesIncludedInAccumulatedOtherComprehensiveIncomeAbstract_2A7E7A3C53DEE3246CD622114FD74335" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_ComponentsOfNetUnrealizedGainOnSecuritiesIncludedInAccumulatedOtherComprehensiveIncomeAbstract_910377BB99638F4A3CFD22114FD7452A" xlink:to="loc_afg_UnrealizedGainOnSecuritiesIncludedInAccumulatedOtherComprehensiveIncomeAbstract_2A7E7A3C53DEE3246CD622114FD74335" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentPretax" xlink:label="loc_afg_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentPretax_D53A3DA11FB443577FE822114FD7FB07" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_UnrealizedGainOnSecuritiesIncludedInAccumulatedOtherComprehensiveIncomeAbstract_2A7E7A3C53DEE3246CD622114FD74335" xlink:to="loc_afg_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentPretax_D53A3DA11FB443577FE822114FD7FB07" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentDeferredTaxAndNonControllingInterest" xlink:label="loc_afg_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentDeferredTaxAndNonControllingInterest_957905191AD2FF1F194622114FD7B417" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_UnrealizedGainOnSecuritiesIncludedInAccumulatedOtherComprehensiveIncomeAbstract_2A7E7A3C53DEE3246CD622114FD74335" xlink:to="loc_afg_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentDeferredTaxAndNonControllingInterest_957905191AD2FF1F194622114FD7B417" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_DD2109BD38773D3BEB2F22114FD7F943" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_UnrealizedGainOnSecuritiesIncludedInAccumulatedOtherComprehensiveIncomeAbstract_2A7E7A3C53DEE3246CD622114FD74335" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax_DD2109BD38773D3BEB2F22114FD7F943" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/InvestmentsDetails5" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems" xlink:label="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems_91DA59C60292DA3357B022114E529EAD" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryTable" xlink:label="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryTable_5A5B4FCF5291DDE8C11A22114E519CDD" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems_91DA59C60292DA3357B022114E529EAD" xlink:to="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryTable_5A5B4FCF5291DDE8C11A22114E519CDD" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InvestmentTypeAxis" xlink:label="loc_us-gaap_InvestmentTypeAxis_84ABB387EDC2AA1DB3A322114E51338F" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryTable_5A5B4FCF5291DDE8C11A22114E519CDD" xlink:to="loc_us-gaap_InvestmentTypeAxis_84ABB387EDC2AA1DB3A322114E51338F" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_A34F52C8CC09BFA1EAF322114E515171_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InvestmentTypeAxis_84ABB387EDC2AA1DB3A322114E51338F" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_A34F52C8CC09BFA1EAF322114E515171_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="loc_us-gaap_InvestmentTypeCategorizationMember_A34F52C8CC09BFA1EAF322114E515171" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InvestmentTypeAxis_84ABB387EDC2AA1DB3A322114E51338F" xlink:to="loc_us-gaap_InvestmentTypeCategorizationMember_A34F52C8CC09BFA1EAF322114E515171" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FixedMaturitiesMember" xlink:label="loc_us-gaap_FixedMaturitiesMember_CA3C377708913E0FC46822114E51CD4A" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_A34F52C8CC09BFA1EAF322114E515171" xlink:to="loc_us-gaap_FixedMaturitiesMember_CA3C377708913E0FC46822114E51CD4A" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EquitySecuritiesMember" xlink:label="loc_us-gaap_EquitySecuritiesMember_086DD7E5044DDBC9FDDA22114E522870" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_A34F52C8CC09BFA1EAF322114E515171" xlink:to="loc_us-gaap_EquitySecuritiesMember_086DD7E5044DDBC9FDDA22114E522870" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EquityMethodInvestmentsMember" xlink:label="loc_us-gaap_EquityMethodInvestmentsMember_A4E15A1FEE7F278BEAE322114E523922" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_A34F52C8CC09BFA1EAF322114E515171" xlink:to="loc_us-gaap_EquityMethodInvestmentsMember_A4E15A1FEE7F278BEAE322114E523922" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherLongTermInvestmentsMember" xlink:label="loc_us-gaap_OtherLongTermInvestmentsMember_449C96E1C3D44923C7AA22114E52F8F2" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentTypeCategorizationMember_A34F52C8CC09BFA1EAF322114E515171" xlink:to="loc_us-gaap_OtherLongTermInvestmentsMember_449C96E1C3D44923C7AA22114E52F8F2" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_GrossInvestmentIncomeOperating" xlink:label="loc_us-gaap_GrossInvestmentIncomeOperating_BD025FF94140655E7A8B22114E528E77" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems_91DA59C60292DA3357B022114E529EAD" xlink:to="loc_us-gaap_GrossInvestmentIncomeOperating_BD025FF94140655E7A8B22114E528E77" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InvestmentIncomeInvestmentExpense" xlink:label="loc_us-gaap_InvestmentIncomeInvestmentExpense_D2B4C69C6103A00935AA22114E52AF5B" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems_91DA59C60292DA3357B022114E529EAD" xlink:to="loc_us-gaap_InvestmentIncomeInvestmentExpense_D2B4C69C6103A00935AA22114E52AF5B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NetInvestmentIncome" xlink:label="loc_us-gaap_NetInvestmentIncome_369F5A733F749AFE4E3122114E52E9DC" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems_91DA59C60292DA3357B022114E529EAD" xlink:to="loc_us-gaap_NetInvestmentIncome_369F5A733F749AFE4E3122114E52E9DC" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/InvestmentsDetails6" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_DD6E09A6D03C5D2F924741D56570289C" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesTable" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_7E252635073E2235B2DE41D5656F1199" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_DD6E09A6D03C5D2F924741D56570289C" xlink:to="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_7E252635073E2235B2DE41D5656F1199" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_6CB04D51BC0F1420D22D41D5656FF040" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_7E252635073E2235B2DE41D5656F1199" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_6CB04D51BC0F1420D22D41D5656FF040" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_50D59EA7C1180578EC2C41D56570D711_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_6CB04D51BC0F1420D22D41D5656FF040" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_50D59EA7C1180578EC2C41D56570D711_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_50D59EA7C1180578EC2C41D56570D711" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_6CB04D51BC0F1420D22D41D5656FF040" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_50D59EA7C1180578EC2C41D56570D711" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FixedMaturitiesMember" xlink:label="loc_us-gaap_FixedMaturitiesMember_D53D998C1FD19905AC1941D565703ED6" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_50D59EA7C1180578EC2C41D56570D711" xlink:to="loc_us-gaap_FixedMaturitiesMember_D53D998C1FD19905AC1941D565703ED6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EquitySecuritiesMember" xlink:label="loc_us-gaap_EquitySecuritiesMember_B983A864C1D41E0A657741D56570763E" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_50D59EA7C1180578EC2C41D56570D711" xlink:to="loc_us-gaap_EquitySecuritiesMember_B983A864C1D41E0A657741D56570763E" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_MortgageLoansAndOtherInvestmentsMember" xlink:label="loc_afg_MortgageLoansAndOtherInvestmentsMember_2661BB4F302E6EBA228D41D565702708" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_50D59EA7C1180578EC2C41D56570D711" xlink:to="loc_afg_MortgageLoansAndOtherInvestmentsMember_2661BB4F302E6EBA228D41D565702708" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_OtherIncludingDPACandReservesonAnnuityandLongtermCareMember" xlink:label="loc_afg_OtherIncludingDPACandReservesonAnnuityandLongtermCareMember_1057D395823B39F9ED674222E05990B6" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_50D59EA7C1180578EC2C41D56570D711" xlink:to="loc_afg_OtherIncludingDPACandReservesonAnnuityandLongtermCareMember_1057D395823B39F9ED674222E05990B6" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_TaxEffectsMember" xlink:label="loc_afg_TaxEffectsMember_45A29D66F719ED8F714F41D565703467" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_50D59EA7C1180578EC2C41D56570D711" xlink:to="loc_afg_TaxEffectsMember_45A29D66F719ED8F714F41D565703467" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NoncontrollingInterestMember" xlink:label="loc_us-gaap_NoncontrollingInterestMember_7DFA866656A408FD422441D5657068C5" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_50D59EA7C1180578EC2C41D56570D711" xlink:to="loc_us-gaap_NoncontrollingInterestMember_7DFA866656A408FD422441D5657068C5" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_MarketableSecuritiesMember" xlink:label="loc_afg_MarketableSecuritiesMember_BA24AB4F98073463C4FC41D56570FF13" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_50D59EA7C1180578EC2C41D56570D711" xlink:to="loc_afg_MarketableSecuritiesMember_BA24AB4F98073463C4FC41D56570FF13" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_RealizedGainsLossesAndChangesInUnrealizedAppreciationDepreciationRelatedToFixedMaturityAndEquitySecurityInvestmentsAbstract" xlink:label="loc_afg_RealizedGainsLossesAndChangesInUnrealizedAppreciationDepreciationRelatedToFixedMaturityAndEquitySecurityInvestmentsAbstract_C4B7E54F2DCB755FECC941D56570E74B" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_DD6E09A6D03C5D2F924741D56570289C" xlink:to="loc_afg_RealizedGainsLossesAndChangesInUnrealizedAppreciationDepreciationRelatedToFixedMaturityAndEquitySecurityInvestmentsAbstract_C4B7E54F2DCB755FECC941D56570E74B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MarketableSecuritiesRealizedGainLossExcludingOtherThanTemporaryImpairments" xlink:label="loc_us-gaap_MarketableSecuritiesRealizedGainLossExcludingOtherThanTemporaryImpairments_049A97DC9BE085F5619741D56570E900" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_RealizedGainsLossesAndChangesInUnrealizedAppreciationDepreciationRelatedToFixedMaturityAndEquitySecurityInvestmentsAbstract_C4B7E54F2DCB755FECC941D56570E74B" xlink:to="loc_us-gaap_MarketableSecuritiesRealizedGainLossExcludingOtherThanTemporaryImpairments_049A97DC9BE085F5619741D56570E900" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities" xlink:label="loc_us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities_CEA91126BC538B53F6B441D565709CD5" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_RealizedGainsLossesAndChangesInUnrealizedAppreciationDepreciationRelatedToFixedMaturityAndEquitySecurityInvestmentsAbstract_C4B7E54F2DCB755FECC941D56570E74B" xlink:to="loc_us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities_CEA91126BC538B53F6B441D565709CD5" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_ChangeInUnrealizedAppreciationDepreciation" xlink:label="loc_afg_ChangeInUnrealizedAppreciationDepreciation_5ADEF16BAEEBAD72D9D441D56570D7A1" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_RealizedGainsLossesAndChangesInUnrealizedAppreciationDepreciationRelatedToFixedMaturityAndEquitySecurityInvestmentsAbstract_C4B7E54F2DCB755FECC941D56570E74B" xlink:to="loc_afg_ChangeInUnrealizedAppreciationDepreciation_5ADEF16BAEEBAD72D9D441D56570D7A1" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/InvestmentsDetails7" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_A294CB07783FF909B32B22114E255189" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesTable" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_41EDA5DC477059B7963622114E24C1FA" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_A294CB07783FF909B32B22114E255189" xlink:to="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_41EDA5DC477059B7963622114E24C1FA" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_3E7347D8121E7490C39A22114E24EC86" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesTable_41EDA5DC477059B7963622114E24C1FA" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_3E7347D8121E7490C39A22114E24EC86" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_8D1EAC3A61A569B9CCF022114E24EB3F_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_3E7347D8121E7490C39A22114E24EC86" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_8D1EAC3A61A569B9CCF022114E24EB3F_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_8D1EAC3A61A569B9CCF022114E24EB3F" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_3E7347D8121E7490C39A22114E24EC86" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_8D1EAC3A61A569B9CCF022114E24EB3F" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FixedMaturitiesMember" xlink:label="loc_us-gaap_FixedMaturitiesMember_2F00B32154CBB17443A122114E25273C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_8D1EAC3A61A569B9CCF022114E24EB3F" xlink:to="loc_us-gaap_FixedMaturitiesMember_2F00B32154CBB17443A122114E25273C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_EquitySecuritiesMember" xlink:label="loc_us-gaap_EquitySecuritiesMember_20089BE1298E5BF126B522114E254966" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_8D1EAC3A61A569B9CCF022114E24EB3F" xlink:to="loc_us-gaap_EquitySecuritiesMember_20089BE1298E5BF126B522114E254966" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesGrossRealizedGainLossNetAbstract" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesGrossRealizedGainLossNetAbstract_1981C2837AF6E9145CC522114E25BBBD" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_A294CB07783FF909B32B22114E255189" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesGrossRealizedGainLossNetAbstract_1981C2837AF6E9145CC522114E25BBBD" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesGrossRealizedGains" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesGrossRealizedGains_6B4F207CCAE32778E2A022114E25EC17" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesGrossRealizedGainLossNetAbstract_1981C2837AF6E9145CC522114E25BBBD" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesGrossRealizedGains_6B4F207CCAE32778E2A022114E25EC17" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses_180DD1B347119DB5A1C522114E254C9C" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesGrossRealizedGainLossNetAbstract_1981C2837AF6E9145CC522114E25BBBD" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses_180DD1B347119DB5A1C522114E254C9C" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/InvestmentsDetailsTextual" xlink:type="extended">
    <loc xlink:href="http://xbrl.sec.gov/invest/2013/invest-2013-01-31.xsd#invest_InvestmentLineItems" xlink:label="loc_invest_InvestmentLineItems_3A0982351FAC27CDE0B3AD4A47EAD2BD" xlink:type="locator" />
    <loc xlink:href="http://xbrl.sec.gov/invest/2013/invest-2013-01-31.xsd#invest_InvestmentTable" xlink:label="loc_invest_InvestmentTable_2639FAEA5BC0C1580DF1AD4A47EA1BD2" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_invest_InvestmentLineItems_3A0982351FAC27CDE0B3AD4A47EAD2BD" xlink:to="loc_invest_InvestmentTable_2639FAEA5BC0C1580DF1AD4A47EA1BD2" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_5DAEE4979954F2AD2801AD4A47EA2395" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_invest_InvestmentTable_2639FAEA5BC0C1580DF1AD4A47EA1BD2" xlink:to="loc_us-gaap_RangeAxis_5DAEE4979954F2AD2801AD4A47EA2395" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_6FCCFE84DDC0B44A40E9AD4A47EAC7E0_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_5DAEE4979954F2AD2801AD4A47EA2395" xlink:to="loc_us-gaap_RangeMember_6FCCFE84DDC0B44A40E9AD4A47EAC7E0_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_6FCCFE84DDC0B44A40E9AD4A47EAC7E0" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_5DAEE4979954F2AD2801AD4A47EA2395" xlink:to="loc_us-gaap_RangeMember_6FCCFE84DDC0B44A40E9AD4A47EAC7E0" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_CA8F470A29C6496BF5D7AD4A47EAE3C3" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_6FCCFE84DDC0B44A40E9AD4A47EAC7E0" xlink:to="loc_us-gaap_MaximumMember_CA8F470A29C6496BF5D7AD4A47EAE3C3" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_E15FD8BCD86781FE91F3AD4A47EAC969" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_invest_InvestmentTable_2639FAEA5BC0C1580DF1AD4A47EA1BD2" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_E15FD8BCD86781FE91F3AD4A47EAC969" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_7E1E4F21AD244A0F6B59AD4A47EAD50C_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_E15FD8BCD86781FE91F3AD4A47EAC969" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_7E1E4F21AD244A0F6B59AD4A47EAD50C_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain" xlink:label="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_7E1E4F21AD244A0F6B59AD4A47EAD50C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_E15FD8BCD86781FE91F3AD4A47EAC969" xlink:to="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_7E1E4F21AD244A0F6B59AD4A47EAD50C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ResidentialMortgageBackedSecuritiesMember" xlink:label="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_50FAAD401C7712B7AA45AD4A47EA7610" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_7E1E4F21AD244A0F6B59AD4A47EAD50C" xlink:to="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_50FAAD401C7712B7AA45AD4A47EA7610" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SecuritiesWithNonCreditOtherThanTemporaryImpairmentChargesMember" xlink:label="loc_afg_SecuritiesWithNonCreditOtherThanTemporaryImpairmentChargesMember_6815224408CE1E300F38AD4A47EAE779" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_7E1E4F21AD244A0F6B59AD4A47EAD50C" xlink:to="loc_afg_SecuritiesWithNonCreditOtherThanTemporaryImpairmentChargesMember_6815224408CE1E300F38AD4A47EAE779" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_FixedMaturitiesMember" xlink:label="loc_us-gaap_FixedMaturitiesMember_FF2E5294E1EB67BA51B5AD4A47EA52B4" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MajorTypesOfDebtAndEquitySecuritiesDomain_7E1E4F21AD244A0F6B59AD4A47EAD50C" xlink:to="loc_us-gaap_FixedMaturitiesMember_FF2E5294E1EB67BA51B5AD4A47EA52B4" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_NonCreditRelatedPortionOfOttiChargesTakenForSecuritiesStillOwned" xlink:label="loc_afg_NonCreditRelatedPortionOfOttiChargesTakenForSecuritiesStillOwned_2416108ADA9EDFC090FBAD4A47EADA6B" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_invest_InvestmentLineItems_3A0982351FAC27CDE0B3AD4A47EAD2BD" xlink:to="loc_afg_NonCreditRelatedPortionOfOttiChargesTakenForSecuritiesStillOwned_2416108ADA9EDFC090FBAD4A47EADA6B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_497D42213D2CC89FBF5AAD4A47EACFD4" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_invest_InvestmentLineItems_3A0982351FAC27CDE0B3AD4A47EAD2BD" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_497D42213D2CC89FBF5AAD4A47EACFD4" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_9FCDE5BE4F33D75D060BAD4A47EA5EC5" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_invest_InvestmentLineItems_3A0982351FAC27CDE0B3AD4A47EAD2BD" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_9FCDE5BE4F33D75D060BAD4A47EA5EC5" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_NumberOfAvailableForSaleSecuritiesInUnrealizedLossPosition" xlink:label="loc_afg_NumberOfAvailableForSaleSecuritiesInUnrealizedLossPosition_033C777C637ADA8CD782AD4A47EAAA9D" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_invest_InvestmentLineItems_3A0982351FAC27CDE0B3AD4A47EAD2BD" xlink:to="loc_afg_NumberOfAvailableForSaleSecuritiesInUnrealizedLossPosition_033C777C637ADA8CD782AD4A47EAAA9D" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_PercentageBasedOnUnrealizedLossOfAvailableForSaleFixedMaturitiesThatAreInUnrealizedLossPositionAndRatedInvestmentGrade" xlink:label="loc_afg_PercentageBasedOnUnrealizedLossOfAvailableForSaleFixedMaturitiesThatAreInUnrealizedLossPositionAndRatedInvestmentGrade_97C9E48272086A3C2B90AD4A47EA52BB" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_invest_InvestmentLineItems_3A0982351FAC27CDE0B3AD4A47EAD2BD" xlink:to="loc_afg_PercentageBasedOnUnrealizedLossOfAvailableForSaleFixedMaturitiesThatAreInUnrealizedLossPositionAndRatedInvestmentGrade_97C9E48272086A3C2B90AD4A47EA52BB" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_PercentageBasedOnFairValueOfAvailableForSaleFixedMaturitiesThatAreInUnrealizedLossPositionAndRatedInvestmentGrade" xlink:label="loc_afg_PercentageBasedOnFairValueOfAvailableForSaleFixedMaturitiesThatAreInUnrealizedLossPositionAndRatedInvestmentGrade_56683F98E2FF6815BA55AD4A47EAB7AA" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_invest_InvestmentLineItems_3A0982351FAC27CDE0B3AD4A47EAD2BD" xlink:to="loc_afg_PercentageBasedOnFairValueOfAvailableForSaleFixedMaturitiesThatAreInUnrealizedLossPositionAndRatedInvestmentGrade_56683F98E2FF6815BA55AD4A47EAB7AA" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities" xlink:label="loc_us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities_5028B764BD2DA00D599BAD4A47EA3589" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_invest_InvestmentLineItems_3A0982351FAC27CDE0B3AD4A47EAD2BD" xlink:to="loc_us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities_5028B764BD2DA00D599BAD4A47EA3589" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AssetBackedSecuritiesAverageUsefulLife" xlink:label="loc_afg_AssetBackedSecuritiesAverageUsefulLife_16600C4B169C575341A3AD4A47EA4CE8" xlink:type="locator" />
    <definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_invest_InvestmentLineItems_3A0982351FAC27CDE0B3AD4A47EAD2BD" xlink:to="loc_afg_AssetBackedSecuritiesAverageUsefulLife_16600C4B169C575341A3AD4A47EA4CE8" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_MortgageBackedSecuritiesAverageUsefulLife" xlink:label="loc_afg_MortgageBackedSecuritiesAverageUsefulLife_052143164376E78BABB0AD4A47EA940A" xlink:type="locator" />
    <definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_invest_InvestmentLineItems_3A0982351FAC27CDE0B3AD4A47EAD2BD" xlink:to="loc_afg_MortgageBackedSecuritiesAverageUsefulLife_052143164376E78BABB0AD4A47EA940A" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_InvestmentsInIndividualIssuersAsPercentageOfShareholdersEquity" xlink:label="loc_afg_InvestmentsInIndividualIssuersAsPercentageOfShareholdersEquity_FC664DFEF5D67F746853AD4A47EAD98D" xlink:type="locator" />
    <definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_invest_InvestmentLineItems_3A0982351FAC27CDE0B3AD4A47EAD2BD" xlink:to="loc_afg_InvestmentsInIndividualIssuersAsPercentageOfShareholdersEquity_FC664DFEF5D67F746853AD4A47EAD98D" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/InvestmentsTables" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/LongTermDebt" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/LongTermDebtDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_BCBA0768247CE411089A76F2E35BB0E4" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_9227FB6270234D8E7D8D76F2E35BDAC4" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_BCBA0768247CE411089A76F2E35BB0E4" xlink:to="loc_us-gaap_DebtInstrumentTable_9227FB6270234D8E7D8D76F2E35BDAC4" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_5634384F58EE6EB427EA76F2E35B5E16" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_9227FB6270234D8E7D8D76F2E35BDAC4" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_5634384F58EE6EB427EA76F2E35B5E16" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_F1202EE46F7587E5E9EA76F2E35B3534_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_5634384F58EE6EB427EA76F2E35B5E16" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_F1202EE46F7587E5E9EA76F2E35B3534_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_F1202EE46F7587E5E9EA76F2E35B3534" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_5634384F58EE6EB427EA76F2E35B5E16" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_F1202EE46F7587E5E9EA76F2E35B3534" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SeniorNotesDueInJune2019Member" xlink:label="loc_afg_SeniorNotesDueInJune2019Member_A72A14E417506EFF809D76F2E35BCB69" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_F1202EE46F7587E5E9EA76F2E35B3534" xlink:to="loc_afg_SeniorNotesDueInJune2019Member_A72A14E417506EFF809D76F2E35BCB69" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SeniorNotesDueInJune2042Member" xlink:label="loc_afg_SeniorNotesDueInJune2042Member_BC48AB668ED92BB0B3CE76F2E35B0C9F" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_F1202EE46F7587E5E9EA76F2E35B3534" xlink:to="loc_afg_SeniorNotesDueInJune2042Member_BC48AB668ED92BB0B3CE76F2E35B0C9F" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SeniorNotesDueInAugust2042Member" xlink:label="loc_afg_SeniorNotesDueInAugust2042Member_35DC4B10A03E96469D0276F2E35B0BD0" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_F1202EE46F7587E5E9EA76F2E35B3534" xlink:to="loc_afg_SeniorNotesDueInAugust2042Member_35DC4B10A03E96469D0276F2E35B0BD0" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SeniorNotesDueInSeptember2050Member" xlink:label="loc_afg_SeniorNotesDueInSeptember2050Member_A409170C2B30FF9957A976F2E35B0017" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_F1202EE46F7587E5E9EA76F2E35B3534" xlink:to="loc_afg_SeniorNotesDueInSeptember2050Member_A409170C2B30FF9957A976F2E35B0017" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SubordinatedDebenturesDueInSeptember2054Member" xlink:label="loc_afg_SubordinatedDebenturesDueInSeptember2054Member_48880CBB88AC4A85E9E676F2E35BBD6D" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_F1202EE46F7587E5E9EA76F2E35B3534" xlink:to="loc_afg_SubordinatedDebenturesDueInSeptember2054Member_48880CBB88AC4A85E9E676F2E35BBD6D" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_LegalEntityAxis" xlink:label="loc_dei_LegalEntityAxis_0A7B18A075F255E0231D76F2E35B2B01" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_9227FB6270234D8E7D8D76F2E35BDAC4" xlink:to="loc_dei_LegalEntityAxis_0A7B18A075F255E0231D76F2E35B2B01" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityDomain" xlink:label="loc_dei_EntityDomain_BD403D17C98C0E702A4776F2E35B6D46_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_0A7B18A075F255E0231D76F2E35B2B01" xlink:to="loc_dei_EntityDomain_BD403D17C98C0E702A4776F2E35B6D46_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityDomain" xlink:label="loc_dei_EntityDomain_BD403D17C98C0E702A4776F2E35B6D46" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_0A7B18A075F255E0231D76F2E35B2B01" xlink:to="loc_dei_EntityDomain_BD403D17C98C0E702A4776F2E35B6D46" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ParentCompanyMember" xlink:label="loc_us-gaap_ParentCompanyMember_D4A88E6CA23F413F0F0176F2E35BDA11" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_BD403D17C98C0E702A4776F2E35B6D46" xlink:to="loc_us-gaap_ParentCompanyMember_D4A88E6CA23F413F0F0176F2E35BDA11" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsidiariesMember" xlink:label="loc_us-gaap_SubsidiariesMember_3EB22D5C8D4C7E88BB4376F2E35B19C9" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_BD403D17C98C0E702A4776F2E35B6D46" xlink:to="loc_us-gaap_SubsidiariesMember_3EB22D5C8D4C7E88BB4376F2E35B19C9" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SummaryOfCarryingValueOfLongTermDebtAbstract" xlink:label="loc_afg_SummaryOfCarryingValueOfLongTermDebtAbstract_607B6503309F7EC10DD876F2E35C7023" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_BCBA0768247CE411089A76F2E35BB0E4" xlink:to="loc_afg_SummaryOfCarryingValueOfLongTermDebtAbstract_607B6503309F7EC10DD876F2E35C7023" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SeniorNotes" xlink:label="loc_us-gaap_SeniorNotes_C5B54F82A5F7FA68ADB176F2E35C07AF" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_SummaryOfCarryingValueOfLongTermDebtAbstract_607B6503309F7EC10DD876F2E35C7023" xlink:to="loc_us-gaap_SeniorNotes_C5B54F82A5F7FA68ADB176F2E35C07AF" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherLongTermDebt" xlink:label="loc_us-gaap_OtherLongTermDebt_D5FA5270414B8C5EB16976F2E35C17F5" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_SummaryOfCarryingValueOfLongTermDebtAbstract_607B6503309F7EC10DD876F2E35C7023" xlink:to="loc_us-gaap_OtherLongTermDebt_D5FA5270414B8C5EB16976F2E35C17F5" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongTermDebt" xlink:label="loc_us-gaap_LongTermDebt_3BA252BA3862ECED6F1976F2E35C2349" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_SummaryOfCarryingValueOfLongTermDebtAbstract_607B6503309F7EC10DD876F2E35C7023" xlink:to="loc_us-gaap_LongTermDebt_3BA252BA3862ECED6F1976F2E35C2349" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubordinatedDebt" xlink:label="loc_us-gaap_SubordinatedDebt_C2E6DBAC2264BE7D1CB976F2E35C82E1" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_SummaryOfCarryingValueOfLongTermDebtAbstract_607B6503309F7EC10DD876F2E35C7023" xlink:to="loc_us-gaap_SubordinatedDebt_C2E6DBAC2264BE7D1CB976F2E35C82E1" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_LongTermNotesPayableSecuredByRealEstate" xlink:label="loc_afg_LongTermNotesPayableSecuredByRealEstate_A59ABD84FC69AEAA022976F2E35C6DEF" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_SummaryOfCarryingValueOfLongTermDebtAbstract_607B6503309F7EC10DD876F2E35C7023" xlink:to="loc_afg_LongTermNotesPayableSecuredByRealEstate_A59ABD84FC69AEAA022976F2E35C6DEF" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LoansPayableToBank" xlink:label="loc_us-gaap_LoansPayableToBank_4CD3CE8E826E814B9CF876F2E35CB1C6" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_afg_SummaryOfCarryingValueOfLongTermDebtAbstract_607B6503309F7EC10DD876F2E35C7023" xlink:to="loc_us-gaap_LoansPayableToBank_4CD3CE8E826E814B9CF876F2E35CB1C6" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/LongTermDebtDetails1" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_720586EA77B9770EF6F185CA4F446407" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_D3C002A2FFABDA52717485CA4F449B12" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_720586EA77B9770EF6F185CA4F446407" xlink:to="loc_us-gaap_DebtInstrumentTable_D3C002A2FFABDA52717485CA4F449B12" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_017B126D019136DCD6B485CA4F446E66" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_D3C002A2FFABDA52717485CA4F449B12" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_017B126D019136DCD6B485CA4F446E66" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_95AE90293741E43027C885CA4F44FB3E_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_017B126D019136DCD6B485CA4F446E66" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_95AE90293741E43027C885CA4F44FB3E_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_95AE90293741E43027C885CA4F44FB3E" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_017B126D019136DCD6B485CA4F446E66" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_95AE90293741E43027C885CA4F44FB3E" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SeniorDebtObligationsMember" xlink:label="loc_us-gaap_SeniorDebtObligationsMember_9A189309440B6CF78F2B85CA4F441752" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_95AE90293741E43027C885CA4F44FB3E" xlink:to="loc_us-gaap_SeniorDebtObligationsMember_9A189309440B6CF78F2B85CA4F441752" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubordinatedDebtObligationsMember" xlink:label="loc_us-gaap_SubordinatedDebtObligationsMember_18AC33921FB82329A33885CA4F447C3D" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_95AE90293741E43027C885CA4F44FB3E" xlink:to="loc_us-gaap_SubordinatedDebtObligationsMember_18AC33921FB82329A33885CA4F447C3D" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongTermDebtAbstract" xlink:label="loc_us-gaap_LongTermDebtAbstract_C1C9E567B4589AF61AE685CA4F445D10" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_720586EA77B9770EF6F185CA4F446407" xlink:to="loc_us-gaap_LongTermDebtAbstract_C1C9E567B4589AF61AE685CA4F445D10" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_UnsecuredDebt" xlink:label="loc_us-gaap_UnsecuredDebt_86DE09D75D0D150DB21185CA4F494BE4" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongTermDebtAbstract_C1C9E567B4589AF61AE685CA4F445D10" xlink:to="loc_us-gaap_UnsecuredDebt_86DE09D75D0D150DB21185CA4F494BE4" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SecuredDebt" xlink:label="loc_us-gaap_SecuredDebt_BCA3C961D8CA246D774E85CA518F6445" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongTermDebtAbstract_C1C9E567B4589AF61AE685CA4F445D10" xlink:to="loc_us-gaap_SecuredDebt_BCA3C961D8CA246D774E85CA518F6445" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongTermDebt" xlink:label="loc_us-gaap_LongTermDebt_1F1CD0D1B5AFA167F6FB85CA4F4AC819" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongTermDebtAbstract_C1C9E567B4589AF61AE685CA4F445D10" xlink:to="loc_us-gaap_LongTermDebt_1F1CD0D1B5AFA167F6FB85CA4F4AC819" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/LongTermDebtDetailsTextual" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_CBF5F4ED62818FCCF4AA3E2E513CCC8B" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:to="loc_us-gaap_DebtInstrumentTable_CBF5F4ED62818FCCF4AA3E2E513CCC8B" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_F9690C537589C2C5EF423E2E513C1A5A" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_CBF5F4ED62818FCCF4AA3E2E513CCC8B" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_F9690C537589C2C5EF423E2E513C1A5A" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_0D545291F4A1967D4CEF3E2E513C12A9_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_F9690C537589C2C5EF423E2E513C1A5A" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_0D545291F4A1967D4CEF3E2E513C12A9_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_0D545291F4A1967D4CEF3E2E513C12A9" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_F9690C537589C2C5EF423E2E513C1A5A" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_0D545291F4A1967D4CEF3E2E513C12A9" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SeniorNotesDueInJune2019Member" xlink:label="loc_afg_SeniorNotesDueInJune2019Member_B7505E94BB653B3F212F3E2E513C8964" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_0D545291F4A1967D4CEF3E2E513C12A9" xlink:to="loc_afg_SeniorNotesDueInJune2019Member_B7505E94BB653B3F212F3E2E513C8964" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SeniorNotesDueInJune2042Member" xlink:label="loc_afg_SeniorNotesDueInJune2042Member_BB015AABA06A1D4389263E2E513C9A22" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_0D545291F4A1967D4CEF3E2E513C12A9" xlink:to="loc_afg_SeniorNotesDueInJune2042Member_BB015AABA06A1D4389263E2E513C9A22" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SeniorNotesDueInAugust2042Member" xlink:label="loc_afg_SeniorNotesDueInAugust2042Member_ABDB1C2DAE89A7908DB33E2E513C49F9" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_0D545291F4A1967D4CEF3E2E513C12A9" xlink:to="loc_afg_SeniorNotesDueInAugust2042Member_ABDB1C2DAE89A7908DB33E2E513C49F9" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SeniorNotesDueInSeptember2050Member" xlink:label="loc_afg_SeniorNotesDueInSeptember2050Member_98055DF081EC82E8381B3E2E513C48DF" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_0D545291F4A1967D4CEF3E2E513C12A9" xlink:to="loc_afg_SeniorNotesDueInSeptember2050Member_98055DF081EC82E8381B3E2E513C48DF" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SubordinatedDebenturesDueInSeptember2054Member" xlink:label="loc_afg_SubordinatedDebenturesDueInSeptember2054Member_28A0E8049EFBC74C654C3E963854CB44" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_0D545291F4A1967D4CEF3E2E513C12A9" xlink:to="loc_afg_SubordinatedDebenturesDueInSeptember2054Member_28A0E8049EFBC74C654C3E963854CB44" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_LegalEntityAxis" xlink:label="loc_dei_LegalEntityAxis_D1C59F0B581D75544C623E2E513C4F56" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_CBF5F4ED62818FCCF4AA3E2E513CCC8B" xlink:to="loc_dei_LegalEntityAxis_D1C59F0B581D75544C623E2E513C4F56" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityDomain" xlink:label="loc_dei_EntityDomain_1F4617D952BF09D4ACDB3E2E513C30AA_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_D1C59F0B581D75544C623E2E513C4F56" xlink:to="loc_dei_EntityDomain_1F4617D952BF09D4ACDB3E2E513C30AA_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityDomain" xlink:label="loc_dei_EntityDomain_1F4617D952BF09D4ACDB3E2E513C30AA" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_D1C59F0B581D75544C623E2E513C4F56" xlink:to="loc_dei_EntityDomain_1F4617D952BF09D4ACDB3E2E513C30AA" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ParentCompanyMember" xlink:label="loc_us-gaap_ParentCompanyMember_5B19858C1B5723E2B36B3E2E513CB9FF" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_1F4617D952BF09D4ACDB3E2E513C30AA" xlink:to="loc_us-gaap_ParentCompanyMember_5B19858C1B5723E2B36B3E2E513CB9FF" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_NationalInterstateMember" xlink:label="loc_afg_NationalInterstateMember_8D624B34E8BB77811BEB3E2E514B5045" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_1F4617D952BF09D4ACDB3E2E513C30AA" xlink:to="loc_afg_NationalInterstateMember_8D624B34E8BB77811BEB3E2E514B5045" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_EE3458248422901A3D493E2E514B5A7B" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_CBF5F4ED62818FCCF4AA3E2E513CCC8B" xlink:to="loc_us-gaap_RangeAxis_EE3458248422901A3D493E2E514B5A7B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_853E7929D707205A01303E2E514B8E36_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RangeAxis_EE3458248422901A3D493E2E514B5A7B" xlink:to="loc_us-gaap_RangeMember_853E7929D707205A01303E2E514B8E36_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_853E7929D707205A01303E2E514B8E36" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RangeAxis_EE3458248422901A3D493E2E514B5A7B" xlink:to="loc_us-gaap_RangeMember_853E7929D707205A01303E2E514B8E36" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_3959F9B78998AE7805D03E2E514B6149" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_853E7929D707205A01303E2E514B8E36" xlink:to="loc_us-gaap_MinimumMember_3959F9B78998AE7805D03E2E514B6149" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_5850AB44E29F410CCB4D3E2E514BDD79" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RangeMember_853E7929D707205A01303E2E514B8E36" xlink:to="loc_us-gaap_MaximumMember_5850AB44E29F410CCB4D3E2E514BDD79" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear_02CA43917F5736D4D4AF3E2E514BA1AB" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear_02CA43917F5736D4D4AF3E2E514BA1AB" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_1AF716C70F6DC7FD01203E2E514BCF88" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_1AF716C70F6DC7FD01203E2E514BCF88" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_C52562FAAF7A9BD927003E2E514B8B6C" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_C52562FAAF7A9BD927003E2E514B8B6C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour_1BE5F77C5F65A49DBD0C3E2E514B413A" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour_1BE5F77C5F65A49DBD0C3E2E514B413A" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive_D54905A6AB2DD244A81F3E2E514B9ACF" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:to="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive_D54905A6AB2DD244A81F3E2E514B9ACF" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearSix" xlink:label="loc_afg_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearSix_671BA4DA845C92F90B703E2E514B6BC4" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:to="loc_afg_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearSix_671BA4DA845C92F90B703E2E514B6BC4" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearSix" xlink:label="loc_afg_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearSix_F8EACFEE1B94144427103E2E514BD58A" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:to="loc_afg_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearSix_F8EACFEE1B94144427103E2E514BD58A" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_32C578C92C7BF156DD1E3E2E514BF9B8" xlink:type="locator" />
    <definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_32C578C92C7BF156DD1E3E2E514BF9B8" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_0BAAD78705C6487244663E2E514B381B" xlink:type="locator" />
    <definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_0BAAD78705C6487244663E2E514B381B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LineOfCredit" xlink:label="loc_us-gaap_LineOfCredit_2AF073C727576B857C763E2E514B57FD" xlink:type="locator" />
    <definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:to="loc_us-gaap_LineOfCredit_2AF073C727576B857C763E2E514B57FD" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LoansPayableToBank" xlink:label="loc_us-gaap_LoansPayableToBank_0CFC3E9326F63493F6DF3E2E514B0837" xlink:type="locator" />
    <definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:to="loc_us-gaap_LoansPayableToBank_0CFC3E9326F63493F6DF3E2E514B0837" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubordinatedDebt" xlink:label="loc_us-gaap_SubordinatedDebt_8DDF5DA35AF0A6539DCC3EA59EFAF033" xlink:type="locator" />
    <definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:to="loc_us-gaap_SubordinatedDebt_8DDF5DA35AF0A6539DCC3EA59EFAF033" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SeniorNotes" xlink:label="loc_us-gaap_SeniorNotes_E3537900F3DFD278FF633EA825F5B086" xlink:type="locator" />
    <definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:to="loc_us-gaap_SeniorNotes_E3537900F3DFD278FF633EA825F5B086" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LineOfCreditFacilityInterestRateDescription" xlink:label="loc_us-gaap_LineOfCreditFacilityInterestRateDescription_B49BBEF484B9C167AF493E2E514B6EAD" xlink:type="locator" />
    <definitionArc order="14" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:to="loc_us-gaap_LineOfCreditFacilityInterestRateDescription_B49BBEF484B9C167AF493E2E514B6EAD" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_96234403007E6169BAAD3E2E514B7B40" xlink:type="locator" />
    <definitionArc order="15" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_61BC87DC2AF74D1536F93E2E514BEA50" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_96234403007E6169BAAD3E2E514B7B40" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/LongTermDebtTables" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/ManagedInvestmentEntities" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/ManagedInvestmentEntitiesDetails" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/ManagedInvestmentEntitiesDetailsTextual" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_VariableInterestEntityLineItems" xlink:label="loc_us-gaap_VariableInterestEntityLineItems_7C754DB1320EA4D93339A2AA55105C34" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfVariableInterestEntitiesTable" xlink:label="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_259AC9FA1D1BE40454BAA2AA5510C193" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_7C754DB1320EA4D93339A2AA55105C34" xlink:to="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_259AC9FA1D1BE40454BAA2AA5510C193" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_5FB5401D5C0F9A064005A2AA55105458" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_259AC9FA1D1BE40454BAA2AA5510C193" xlink:to="loc_us-gaap_DebtInstrumentAxis_5FB5401D5C0F9A064005A2AA55105458" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_FD3963AFD239BB6A8513A2AA551077F1_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_5FB5401D5C0F9A064005A2AA55105458" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_FD3963AFD239BB6A8513A2AA551077F1_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_FD3963AFD239BB6A8513A2AA551077F1" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_5FB5401D5C0F9A064005A2AA55105458" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_FD3963AFD239BB6A8513A2AA551077F1" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubordinatedDebtObligationsMember" xlink:label="loc_us-gaap_SubordinatedDebtObligationsMember_957E90369A2E1F41109CA2AA5510634A" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_FD3963AFD239BB6A8513A2AA551077F1" xlink:to="loc_us-gaap_SubordinatedDebtObligationsMember_957E90369A2E1F41109CA2AA5510634A" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SeniorDebtObligationsMember" xlink:label="loc_us-gaap_SeniorDebtObligationsMember_229BFA0A9B93128036ADA2AA5510677E" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_FD3963AFD239BB6A8513A2AA551077F1" xlink:to="loc_us-gaap_SeniorDebtObligationsMember_229BFA0A9B93128036ADA2AA5510677E" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis" xlink:label="loc_us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis_5D73BD97D9282C429736A2AA55100430" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfVariableInterestEntitiesTable_259AC9FA1D1BE40454BAA2AA5510C193" xlink:to="loc_us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis_5D73BD97D9282C429736A2AA55100430" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassificationOfVariableInterestEntityDomain" xlink:label="loc_us-gaap_ClassificationOfVariableInterestEntityDomain_8D143E601997BCF6D548A2AA55102A00_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis_5D73BD97D9282C429736A2AA55100430" xlink:to="loc_us-gaap_ClassificationOfVariableInterestEntityDomain_8D143E601997BCF6D548A2AA55102A00_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassificationOfVariableInterestEntityDomain" xlink:label="loc_us-gaap_ClassificationOfVariableInterestEntityDomain_8D143E601997BCF6D548A2AA55102A00" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis_5D73BD97D9282C429736A2AA55100430" xlink:to="loc_us-gaap_ClassificationOfVariableInterestEntityDomain_8D143E601997BCF6D548A2AA55102A00" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_VariableInterestEntityPrimaryBeneficiaryMember" xlink:label="loc_us-gaap_VariableInterestEntityPrimaryBeneficiaryMember_67D0E0E27B0B40BF13B1A2AA5510B155" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassificationOfVariableInterestEntityDomain_8D143E601997BCF6D548A2AA55102A00" xlink:to="loc_us-gaap_VariableInterestEntityPrimaryBeneficiaryMember_67D0E0E27B0B40BF13B1A2AA5510B155" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_NewCollateralizedLoanObligationEntitiesMember" xlink:label="loc_afg_NewCollateralizedLoanObligationEntitiesMember_C2DE15D23FD3DD146142A2B6EA15206B" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassificationOfVariableInterestEntityDomain_8D143E601997BCF6D548A2AA55102A00" xlink:to="loc_afg_NewCollateralizedLoanObligationEntitiesMember_C2DE15D23FD3DD146142A2B6EA15206B" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_PercentageOfInvestmentOfMostSubordinateDebtTrancheOfVariableInterestEntityMinimum" xlink:label="loc_afg_PercentageOfInvestmentOfMostSubordinateDebtTrancheOfVariableInterestEntityMinimum_5ECD086754A6303A0913A2AA55104539" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_7C754DB1320EA4D93339A2AA55105C34" xlink:to="loc_afg_PercentageOfInvestmentOfMostSubordinateDebtTrancheOfVariableInterestEntityMinimum_5ECD086754A6303A0913A2AA55104539" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_PercentageOfInvestmentOfMostSubordinateDebtTrancheOfVariableInterestEntityMaximum" xlink:label="loc_afg_PercentageOfInvestmentOfMostSubordinateDebtTrancheOfVariableInterestEntityMaximum_C130B2305D952CC611EAA2AA55107793" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_7C754DB1320EA4D93339A2AA55105C34" xlink:to="loc_afg_PercentageOfInvestmentOfMostSubordinateDebtTrancheOfVariableInterestEntityMaximum_C130B2305D952CC611EAA2AA55107793" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_NumberOfCollateralizedLoanObligationEntities" xlink:label="loc_afg_NumberOfCollateralizedLoanObligationEntities_684482E929457B84F4DCA2AA5510E0F9" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_7C754DB1320EA4D93339A2AA55105C34" xlink:to="loc_afg_NumberOfCollateralizedLoanObligationEntities_684482E929457B84F4DCA2AA5510E0F9" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_VariableInterestEntityEntityMaximumLossExposureAmount" xlink:label="loc_us-gaap_VariableInterestEntityEntityMaximumLossExposureAmount_540CBE5C779B142AA1A2A2AA5510586D" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_7C754DB1320EA4D93339A2AA55105C34" xlink:to="loc_us-gaap_VariableInterestEntityEntityMaximumLossExposureAmount_540CBE5C779B142AA1A2A2AA5510586D" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FaceValueOfLiabilitiesIssuedByManagedInvestmentEntitiesOnIssuanceDate" xlink:label="loc_afg_FaceValueOfLiabilitiesIssuedByManagedInvestmentEntitiesOnIssuanceDate_C6620F5F78471E007927A2AE38E3C371" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_7C754DB1320EA4D93339A2AA55105C34" xlink:to="loc_afg_FaceValueOfLiabilitiesIssuedByManagedInvestmentEntitiesOnIssuanceDate_C6620F5F78471E007927A2AE38E3C371" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FaceAmountOfManagedInvestmentEntitiesLiabilitiesPurchasedBySubsidiariesAtIssuanceDate" xlink:label="loc_afg_FaceAmountOfManagedInvestmentEntitiesLiabilitiesPurchasedBySubsidiariesAtIssuanceDate_B83FE52C3A9FF2F3F2C0A2BBBA78A29B" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_7C754DB1320EA4D93339A2AA55105C34" xlink:to="loc_afg_FaceAmountOfManagedInvestmentEntitiesLiabilitiesPurchasedBySubsidiariesAtIssuanceDate_B83FE52C3A9FF2F3F2C0A2BBBA78A29B" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_FaceAmountOfManagedInvestmentEntitiesLiabilitiesPurchasedBySubsidiariesAfterIssuanceDate" xlink:label="loc_afg_FaceAmountOfManagedInvestmentEntitiesLiabilitiesPurchasedBySubsidiariesAfterIssuanceDate_D9530FBDA05873A992F5A2AA55104645" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_7C754DB1320EA4D93339A2AA55105C34" xlink:to="loc_afg_FaceAmountOfManagedInvestmentEntitiesLiabilitiesPurchasedBySubsidiariesAfterIssuanceDate_D9530FBDA05873A992F5A2AA55104645" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AmountPaidBySubsidiariesToPurchaseManagedInvestmentEntitiesLiabilitiesAfterIssuanceDate." xlink:label="loc_afg_AmountPaidBySubsidiariesToPurchaseManagedInvestmentEntitiesLiabilitiesAfterIssuanceDate._C73F03CBD96714FAC8B8A2AA5510167C" xlink:type="locator" />
    <definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_7C754DB1320EA4D93339A2AA55105C34" xlink:to="loc_afg_AmountPaidBySubsidiariesToPurchaseManagedInvestmentEntitiesLiabilitiesAfterIssuanceDate._C73F03CBD96714FAC8B8A2AA5510167C" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_ProceedsReceivedBySubsidiariesRelatedtoRedemptionsofManagedInvestmentEntitiesLiabilities" xlink:label="loc_afg_ProceedsReceivedBySubsidiariesRelatedtoRedemptionsofManagedInvestmentEntitiesLiabilities_3CD8ED58662A801A7854A2AA55109AAB" xlink:type="locator" />
    <definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_7C754DB1320EA4D93339A2AA55105C34" xlink:to="loc_afg_ProceedsReceivedBySubsidiariesRelatedtoRedemptionsofManagedInvestmentEntitiesLiabilities_3CD8ED58662A801A7854A2AA55109AAB" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_DifferenceBetweenAggregateUnpaidPrincipalBalanceAndFairValueOfVariableInterestEntityInvestments" xlink:label="loc_afg_DifferenceBetweenAggregateUnpaidPrincipalBalanceAndFairValueOfVariableInterestEntityInvestments_D39454B6AF11BA056180A2AA55102BCF" xlink:type="locator" />
    <definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_7C754DB1320EA4D93339A2AA55105C34" xlink:to="loc_afg_DifferenceBetweenAggregateUnpaidPrincipalBalanceAndFairValueOfVariableInterestEntityInvestments_D39454B6AF11BA056180A2AA55102BCF" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_DifferenceBetweenAggregateUnpaidPrincipalBalanceAndFairValueOfVariableInterestEntityDebt" xlink:label="loc_afg_DifferenceBetweenAggregateUnpaidPrincipalBalanceAndFairValueOfVariableInterestEntityDebt_AB0C990F3A1FEA4F4D83A2AA551097A0" xlink:type="locator" />
    <definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_7C754DB1320EA4D93339A2AA55105C34" xlink:to="loc_afg_DifferenceBetweenAggregateUnpaidPrincipalBalanceAndFairValueOfVariableInterestEntityDebt_AB0C990F3A1FEA4F4D83A2AA551097A0" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_CarryingAmountOfVariableInterestEntityLoansInDefault" xlink:label="loc_afg_CarryingAmountOfVariableInterestEntityLoansInDefault_17D32E9F53EF4D1EEA4EA2AA55106E8B" xlink:type="locator" />
    <definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_7C754DB1320EA4D93339A2AA55105C34" xlink:to="loc_afg_CarryingAmountOfVariableInterestEntityLoansInDefault_17D32E9F53EF4D1EEA4EA2AA55106E8B" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AggregateUnpaidPrincipalBalanceOfVariableInterestEntityLoansInDefault" xlink:label="loc_afg_AggregateUnpaidPrincipalBalanceOfVariableInterestEntityLoansInDefault_5CD16EAAE134428B44EBA2AA5510E79E" xlink:type="locator" />
    <definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableInterestEntityLineItems_7C754DB1320EA4D93339A2AA55105C34" xlink:to="loc_afg_AggregateUnpaidPrincipalBalanceOfVariableInterestEntityLoansInDefault_5CD16EAAE134428B44EBA2AA5510E79E" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/ManagedInvestmentEntitiesTables" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/SegmentsOfOperations" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/SegmentsOfOperationsDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_0E8D79EC9DFA8D08770475F55D899AAC" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_35A2F3B8B7D603C9850375F55D89BB8A" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_0E8D79EC9DFA8D08770475F55D899AAC" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_35A2F3B8B7D603C9850375F55D89BB8A" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsegmentsAxis" xlink:label="loc_us-gaap_SubsegmentsAxis_ADB5BC251B203D96572675F55D893E3F" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_35A2F3B8B7D603C9850375F55D89BB8A" xlink:to="loc_us-gaap_SubsegmentsAxis_ADB5BC251B203D96572675F55D893E3F" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsegmentsDomain" xlink:label="loc_us-gaap_SubsegmentsDomain_2551BC6C638C911FB55975F55D89A8B4_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsegmentsAxis_ADB5BC251B203D96572675F55D893E3F" xlink:to="loc_us-gaap_SubsegmentsDomain_2551BC6C638C911FB55975F55D89A8B4_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsegmentsDomain" xlink:label="loc_us-gaap_SubsegmentsDomain_2551BC6C638C911FB55975F55D89A8B4" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsegmentsAxis_ADB5BC251B203D96572675F55D893E3F" xlink:to="loc_us-gaap_SubsegmentsDomain_2551BC6C638C911FB55975F55D89A8B4" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SpecialtyPropertyAndTransportationInsuranceMember" xlink:label="loc_afg_SpecialtyPropertyAndTransportationInsuranceMember_8FC4A2C0E8E42752453175F55D8987E7" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsegmentsDomain_2551BC6C638C911FB55975F55D89A8B4" xlink:to="loc_afg_SpecialtyPropertyAndTransportationInsuranceMember_8FC4A2C0E8E42752453175F55D8987E7" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SpecialtyCasualtyInsuranceMember" xlink:label="loc_afg_SpecialtyCasualtyInsuranceMember_155B7FFF701607BE3D7A75F55D89721A" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsegmentsDomain_2551BC6C638C911FB55975F55D89A8B4" xlink:to="loc_afg_SpecialtyCasualtyInsuranceMember_155B7FFF701607BE3D7A75F55D89721A" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SpecialtyFinancialInsuranceMember" xlink:label="loc_afg_SpecialtyFinancialInsuranceMember_05A4D891CECF4704508F75F55D89E914" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsegmentsDomain_2551BC6C638C911FB55975F55D89A8B4" xlink:to="loc_afg_SpecialtyFinancialInsuranceMember_05A4D891CECF4704508F75F55D89E914" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SpecialtyOtherInsuranceMember" xlink:label="loc_afg_SpecialtyOtherInsuranceMember_8387A3645F3E9CA15B3575F55D8947BE" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsegmentsDomain_2551BC6C638C911FB55975F55D89A8B4" xlink:to="loc_afg_SpecialtyOtherInsuranceMember_8387A3645F3E9CA15B3575F55D8947BE" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_E20318FC550162AC91C075F55D892E07" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_35A2F3B8B7D603C9850375F55D89BB8A" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_E20318FC550162AC91C075F55D892E07" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_243A2121E7472534484675F55D89E39D_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_E20318FC550162AC91C075F55D892E07" xlink:to="loc_us-gaap_SegmentDomain_243A2121E7472534484675F55D89E39D_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_243A2121E7472534484675F55D89E39D" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_E20318FC550162AC91C075F55D892E07" xlink:to="loc_us-gaap_SegmentDomain_243A2121E7472534484675F55D89E39D" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_PropertyAndCasualtyInsuranceMember" xlink:label="loc_afg_PropertyAndCasualtyInsuranceMember_F9EC9D7517364890756D75F55D898E30" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_243A2121E7472534484675F55D89E39D" xlink:to="loc_afg_PropertyAndCasualtyInsuranceMember_F9EC9D7517364890756D75F55D898E30" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AnnuityMember" xlink:label="loc_afg_AnnuityMember_C3EB63F57FA16EF0E98375F55D89F920" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_243A2121E7472534484675F55D89E39D" xlink:to="loc_afg_AnnuityMember_C3EB63F57FA16EF0E98375F55D89F920" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_RunOffLongTermCareAndLifeMember" xlink:label="loc_afg_RunOffLongTermCareAndLifeMember_4C726E7BC145F9695E1675F55D89AD1D" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_243A2121E7472534484675F55D89E39D" xlink:to="loc_afg_RunOffLongTermCareAndLifeMember_4C726E7BC145F9695E1675F55D89AD1D" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CorporateAndOtherMember" xlink:label="loc_us-gaap_CorporateAndOtherMember_44CEAAEDA2AD6416D0F975F55D896F36" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_243A2121E7472534484675F55D89E39D" xlink:to="loc_us-gaap_CorporateAndOtherMember_44CEAAEDA2AD6416D0F975F55D896F36" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PremiumsEarnedNetPropertyAndCasualty" xlink:label="loc_us-gaap_PremiumsEarnedNetPropertyAndCasualty_BF0E5CB1288C40004BFA75F55D89E620" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_0E8D79EC9DFA8D08770475F55D899AAC" xlink:to="loc_us-gaap_PremiumsEarnedNetPropertyAndCasualty_BF0E5CB1288C40004BFA75F55D89E620" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NetInvestmentIncome" xlink:label="loc_us-gaap_NetInvestmentIncome_292B479B90DA2367543875F55D8975E2" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_0E8D79EC9DFA8D08770475F55D899AAC" xlink:to="loc_us-gaap_NetInvestmentIncome_292B479B90DA2367543875F55D8975E2" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherIncome" xlink:label="loc_us-gaap_OtherIncome_9FFB371427BF4AFC73D375F55D89FF67" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_0E8D79EC9DFA8D08770475F55D899AAC" xlink:to="loc_us-gaap_OtherIncome_9FFB371427BF4AFC73D375F55D89FF67" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_RevenuesBeforeRealizedGainsLosses" xlink:label="loc_afg_RevenuesBeforeRealizedGainsLosses_B86A216A40E519202A4075F55D89AB8E" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_0E8D79EC9DFA8D08770475F55D899AAC" xlink:to="loc_afg_RevenuesBeforeRealizedGainsLosses_B86A216A40E519202A4075F55D89AB8E" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MarketableSecuritiesRealizedGainLoss" xlink:label="loc_us-gaap_MarketableSecuritiesRealizedGainLoss_1B38EE2E6EF4D272A9CB75F55D89252B" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_0E8D79EC9DFA8D08770475F55D899AAC" xlink:to="loc_us-gaap_MarketableSecuritiesRealizedGainLoss_1B38EE2E6EF4D272A9CB75F55D89252B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_7F13C51AF9FD2818D64F75F55D8930E8" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_0E8D79EC9DFA8D08770475F55D899AAC" xlink:to="loc_us-gaap_Revenues_7F13C51AF9FD2818D64F75F55D8930E8" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/SegmentsOfOperationsDetails1" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_2EC228BBEB6D63950B3F22114ECE6518" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_35DDDA34B0DEEED4041422114ECDED2D" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_2EC228BBEB6D63950B3F22114ECE6518" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_35DDDA34B0DEEED4041422114ECDED2D" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsegmentsAxis" xlink:label="loc_us-gaap_SubsegmentsAxis_8F1D021DC9597A3379BC22114ECD241C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_35DDDA34B0DEEED4041422114ECDED2D" xlink:to="loc_us-gaap_SubsegmentsAxis_8F1D021DC9597A3379BC22114ECD241C" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsegmentsDomain" xlink:label="loc_us-gaap_SubsegmentsDomain_4E1860BCEDF43ECC3D2422114ECDCF98_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsegmentsAxis_8F1D021DC9597A3379BC22114ECD241C" xlink:to="loc_us-gaap_SubsegmentsDomain_4E1860BCEDF43ECC3D2422114ECDCF98_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsegmentsDomain" xlink:label="loc_us-gaap_SubsegmentsDomain_4E1860BCEDF43ECC3D2422114ECDCF98" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsegmentsAxis_8F1D021DC9597A3379BC22114ECD241C" xlink:to="loc_us-gaap_SubsegmentsDomain_4E1860BCEDF43ECC3D2422114ECDCF98" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SpecialtyPropertyAndTransportationInsuranceMember" xlink:label="loc_afg_SpecialtyPropertyAndTransportationInsuranceMember_A2FE19624F5CA5B5555C22114ECEB1B1" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsegmentsDomain_4E1860BCEDF43ECC3D2422114ECDCF98" xlink:to="loc_afg_SpecialtyPropertyAndTransportationInsuranceMember_A2FE19624F5CA5B5555C22114ECEB1B1" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SpecialtyCasualtyInsuranceMember" xlink:label="loc_afg_SpecialtyCasualtyInsuranceMember_555DD550C3AFE370781222114ECEFFC1" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsegmentsDomain_4E1860BCEDF43ECC3D2422114ECDCF98" xlink:to="loc_afg_SpecialtyCasualtyInsuranceMember_555DD550C3AFE370781222114ECEFFC1" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SpecialtyFinancialInsuranceMember" xlink:label="loc_afg_SpecialtyFinancialInsuranceMember_9AF13B888C2996F9644722114ECE8AB4" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsegmentsDomain_4E1860BCEDF43ECC3D2422114ECDCF98" xlink:to="loc_afg_SpecialtyFinancialInsuranceMember_9AF13B888C2996F9644722114ECE8AB4" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SpecialtyOtherInsuranceMember" xlink:label="loc_afg_SpecialtyOtherInsuranceMember_59EE5F4A05494C6514DD22114ECE935F" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsegmentsDomain_4E1860BCEDF43ECC3D2422114ECDCF98" xlink:to="loc_afg_SpecialtyOtherInsuranceMember_59EE5F4A05494C6514DD22114ECE935F" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_OtherLinesMember" xlink:label="loc_afg_OtherLinesMember_D7E7E156A94B69CA281C22114ECE7A60" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsegmentsDomain_4E1860BCEDF43ECC3D2422114ECDCF98" xlink:to="loc_afg_OtherLinesMember_D7E7E156A94B69CA281C22114ECE7A60" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_253E4055320A71246E1E22114ECEC41E" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_35DDDA34B0DEEED4041422114ECDED2D" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_253E4055320A71246E1E22114ECEC41E" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_85A24D6CCEAC4534B68F22114ECE1F1A_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_253E4055320A71246E1E22114ECEC41E" xlink:to="loc_us-gaap_SegmentDomain_85A24D6CCEAC4534B68F22114ECE1F1A_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_85A24D6CCEAC4534B68F22114ECE1F1A" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_253E4055320A71246E1E22114ECEC41E" xlink:to="loc_us-gaap_SegmentDomain_85A24D6CCEAC4534B68F22114ECE1F1A" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_PropertyAndCasualtyInsuranceMember" xlink:label="loc_afg_PropertyAndCasualtyInsuranceMember_68F76A3D17E50BD43BB622114ECE5386" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_85A24D6CCEAC4534B68F22114ECE1F1A" xlink:to="loc_afg_PropertyAndCasualtyInsuranceMember_68F76A3D17E50BD43BB622114ECE5386" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AnnuityMember" xlink:label="loc_afg_AnnuityMember_D510E4DB1630016ED9AD22114ECE789B" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_85A24D6CCEAC4534B68F22114ECE1F1A" xlink:to="loc_afg_AnnuityMember_D510E4DB1630016ED9AD22114ECE789B" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_RunOffLongTermCareAndLifeMember" xlink:label="loc_afg_RunOffLongTermCareAndLifeMember_2276DAC48026F21D6FDC22114ECE9CF1" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_85A24D6CCEAC4534B68F22114ECE1F1A" xlink:to="loc_afg_RunOffLongTermCareAndLifeMember_2276DAC48026F21D6FDC22114ECE9CF1" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CorporateAndOtherMember" xlink:label="loc_us-gaap_CorporateAndOtherMember_E8FAC32AAC3F682F4F8B22114ECE06D6" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_85A24D6CCEAC4534B68F22114ECE1F1A" xlink:to="loc_us-gaap_CorporateAndOtherMember_E8FAC32AAC3F682F4F8B22114ECE06D6" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_PropertyAndCasualtyInsuranceUnderwritingIncomeLoss" xlink:label="loc_afg_PropertyAndCasualtyInsuranceUnderwritingIncomeLoss_679ACC0B4D34B8F1D57922114ECE6750" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_2EC228BBEB6D63950B3F22114ECE6518" xlink:to="loc_afg_PropertyAndCasualtyInsuranceUnderwritingIncomeLoss_679ACC0B4D34B8F1D57922114ECE6750" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_InvestmentAndOtherIncomeNet" xlink:label="loc_afg_InvestmentAndOtherIncomeNet_E6D8A0C740698E2DBEEF22114ECE8C62" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_2EC228BBEB6D63950B3F22114ECE6518" xlink:to="loc_afg_InvestmentAndOtherIncomeNet_E6D8A0C740698E2DBEEF22114ECE8C62" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_OperatingIncomeLossBeforeRealizedGainsLossesAndIncomeTaxes" xlink:label="loc_afg_OperatingIncomeLossBeforeRealizedGainsLossesAndIncomeTaxes_355E6D4736C60346DFB822114ECEE6D8" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_2EC228BBEB6D63950B3F22114ECE6518" xlink:to="loc_afg_OperatingIncomeLossBeforeRealizedGainsLossesAndIncomeTaxes_355E6D4736C60346DFB822114ECEE6D8" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MarketableSecuritiesRealizedGainLoss" xlink:label="loc_us-gaap_MarketableSecuritiesRealizedGainLoss_5F9563F2D339BC9C68C522114ECFC5E3" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_2EC228BBEB6D63950B3F22114ECE6518" xlink:to="loc_us-gaap_MarketableSecuritiesRealizedGainLoss_5F9563F2D339BC9C68C522114ECFC5E3" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_28491AB4B7F7509EC4BC22114ECFE64A" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_2EC228BBEB6D63950B3F22114ECE6518" xlink:to="loc_us-gaap_OperatingIncomeLoss_28491AB4B7F7509EC4BC22114ECFE64A" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/SegmentsOfOperationsDetailsTextual" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_10C2EE6204144BDC5620533855902F3E" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_42FF3BC6262C9702DFF65338558F83DE" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_10C2EE6204144BDC5620533855902F3E" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_42FF3BC6262C9702DFF65338558F83DE" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsegmentsAxis" xlink:label="loc_us-gaap_SubsegmentsAxis_C676654CCC45BBB571E95338558F94DD" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_42FF3BC6262C9702DFF65338558F83DE" xlink:to="loc_us-gaap_SubsegmentsAxis_C676654CCC45BBB571E95338558F94DD" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsegmentsDomain" xlink:label="loc_us-gaap_SubsegmentsDomain_D46EF486BB1E8C035C405338558FEC9A_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsegmentsAxis_C676654CCC45BBB571E95338558F94DD" xlink:to="loc_us-gaap_SubsegmentsDomain_D46EF486BB1E8C035C405338558FEC9A_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SubsegmentsDomain" xlink:label="loc_us-gaap_SubsegmentsDomain_D46EF486BB1E8C035C405338558FEC9A" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsegmentsAxis_C676654CCC45BBB571E95338558F94DD" xlink:to="loc_us-gaap_SubsegmentsDomain_D46EF486BB1E8C035C405338558FEC9A" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_OtherLinesMember" xlink:label="loc_afg_OtherLinesMember_ED86915F95BD0F42C2145338558F85B1" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsegmentsDomain_D46EF486BB1E8C035C405338558FEC9A" xlink:to="loc_afg_OtherLinesMember_ED86915F95BD0F42C2145338558F85B1" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LossContingenciesByNatureOfContingencyAxis" xlink:label="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_B44BACF8FFDC7917B85F5338558F24AF" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_42FF3BC6262C9702DFF65338558F83DE" xlink:to="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_B44BACF8FFDC7917B85F5338558F24AF" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LossContingencyNatureDomain" xlink:label="loc_us-gaap_LossContingencyNatureDomain_A1789D3F8B684B6992055338558FB014_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_B44BACF8FFDC7917B85F5338558F24AF" xlink:to="loc_us-gaap_LossContingencyNatureDomain_A1789D3F8B684B6992055338558FB014_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LossContingencyNatureDomain" xlink:label="loc_us-gaap_LossContingencyNatureDomain_A1789D3F8B684B6992055338558FB014" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_B44BACF8FFDC7917B85F5338558F24AF" xlink:to="loc_us-gaap_LossContingencyNatureDomain_A1789D3F8B684B6992055338558FB014" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InsuranceRelatedAssessmentsMember" xlink:label="loc_us-gaap_InsuranceRelatedAssessmentsMember_DA82BF20E2BDDE10BCF95338559028E6" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LossContingencyNatureDomain_A1789D3F8B684B6992055338558FB014" xlink:to="loc_us-gaap_InsuranceRelatedAssessmentsMember_DA82BF20E2BDDE10BCF95338559028E6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_38C6FB9157DFDC910A555338559098D4" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_42FF3BC6262C9702DFF65338558F83DE" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_38C6FB9157DFDC910A555338559098D4" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_FA7ADEA0AB999A3E7FFB53385590CE22_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_38C6FB9157DFDC910A555338559098D4" xlink:to="loc_us-gaap_SegmentDomain_FA7ADEA0AB999A3E7FFB53385590CE22_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_FA7ADEA0AB999A3E7FFB53385590CE22" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_38C6FB9157DFDC910A555338559098D4" xlink:to="loc_us-gaap_SegmentDomain_FA7ADEA0AB999A3E7FFB53385590CE22" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AnnuityMember" xlink:label="loc_afg_AnnuityMember_524C740A9B3818DAB19E5338559096E6" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_FA7ADEA0AB999A3E7FFB53385590CE22" xlink:to="loc_afg_AnnuityMember_524C740A9B3818DAB19E5338559096E6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CorporateAndOtherMember" xlink:label="loc_us-gaap_CorporateAndOtherMember_A1D140BDF5FA236404B1533855907AF8" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_FA7ADEA0AB999A3E7FFB53385590CE22" xlink:to="loc_us-gaap_CorporateAndOtherMember_A1D140BDF5FA236404B1533855907AF8" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NumberOfReportableSegments" xlink:label="loc_us-gaap_NumberOfReportableSegments_AA0DDFB7C7D052E679C653385590068C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_10C2EE6204144BDC5620533855902F3E" xlink:to="loc_us-gaap_NumberOfReportableSegments_AA0DDFB7C7D052E679C653385590068C" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_SpecialChargesToIncreaseAsbestosAndEnvironmentalReserves" xlink:label="loc_afg_SpecialChargesToIncreaseAsbestosAndEnvironmentalReserves_00E87DE48C007B32529D5338559021AE" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_10C2EE6204144BDC5620533855902F3E" xlink:to="loc_afg_SpecialChargesToIncreaseAsbestosAndEnvironmentalReserves_00E87DE48C007B32529D5338559021AE" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LossContingencyLossInPeriod" xlink:label="loc_us-gaap_LossContingencyLossInPeriod_7EC0B7E6731C7F262CF953385590AAB6" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_10C2EE6204144BDC5620533855902F3E" xlink:to="loc_us-gaap_LossContingencyLossInPeriod_7EC0B7E6731C7F262CF953385590AAB6" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_EarningsLossesOfVariableInterestEntitiesAttributableToNoncontrollingInterests" xlink:label="loc_afg_EarningsLossesOfVariableInterestEntitiesAttributableToNoncontrollingInterests_650E8EF63BA69376ED67533855900153" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_10C2EE6204144BDC5620533855902F3E" xlink:to="loc_afg_EarningsLossesOfVariableInterestEntitiesAttributableToNoncontrollingInterests_650E8EF63BA69376ED67533855900153" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/SegmentsOfOperationsTables" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/ShareholdersEquity" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/ShareholdersEquityDetails" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassOfStockLineItems" xlink:label="loc_us-gaap_ClassOfStockLineItems_9A4D1332F03F8A47CDDD57B2EAD9DFB5" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfStockByClassTable" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_60C6F8B0ED1BE1F4B17B57B2EAD9DAA7" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ClassOfStockLineItems_9A4D1332F03F8A47CDDD57B2EAD9DFB5" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_60C6F8B0ED1BE1F4B17B57B2EAD9DAA7" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaap_StatementClassOfStockAxis_80EF704E54E1656FF1F857B2EAD97256" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_60C6F8B0ED1BE1F4B17B57B2EAD9DAA7" xlink:to="loc_us-gaap_StatementClassOfStockAxis_80EF704E54E1656FF1F857B2EAD97256" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaap_ClassOfStockDomain_4321775470F0D74B843757B2EAD9BEFF_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_80EF704E54E1656FF1F857B2EAD97256" xlink:to="loc_us-gaap_ClassOfStockDomain_4321775470F0D74B843757B2EAD9BEFF_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaap_ClassOfStockDomain_4321775470F0D74B843757B2EAD9BEFF" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_80EF704E54E1656FF1F857B2EAD97256" xlink:to="loc_us-gaap_ClassOfStockDomain_4321775470F0D74B843757B2EAD9BEFF" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_VotingPreferredStockMember" xlink:label="loc_afg_VotingPreferredStockMember_4901732CB64EB5601ED257B2EAD9467D" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_4321775470F0D74B843757B2EAD9BEFF" xlink:to="loc_afg_VotingPreferredStockMember_4901732CB64EB5601ED257B2EAD9467D" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_NonvotingPreferredStockMember" xlink:label="loc_afg_NonvotingPreferredStockMember_77613E48D0E499C2270757B2EAD9CFC2" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_4321775470F0D74B843757B2EAD9BEFF" xlink:to="loc_afg_NonvotingPreferredStockMember_77613E48D0E499C2270757B2EAD9CFC2" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PreferredStockNoParValue" xlink:label="loc_us-gaap_PreferredStockNoParValue_00C1C96342EB8945FE3B57B2EAD9349F" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_9A4D1332F03F8A47CDDD57B2EAD9DFB5" xlink:to="loc_us-gaap_PreferredStockNoParValue_00C1C96342EB8945FE3B57B2EAD9349F" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized_7347CADFDAC61A2D7ADD57B2EADA44A9" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_9A4D1332F03F8A47CDDD57B2EAD9DFB5" xlink:to="loc_us-gaap_PreferredStockSharesAuthorized_7347CADFDAC61A2D7ADD57B2EADA44A9" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/ShareholdersEquityDetails1" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/ShareholdersEquityDetails2" xlink:type="extended" />
  <definitionLink xlink:role="http://www.afginc.com/role/ShareholdersEquityDetailsTextual" xlink:type="extended">
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DA7ADF3FB3CCB37CD4E557B2EAC9DA3C" xlink:type="locator" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_508694490B19871D8C3857B2EAC809F8" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DA7ADF3FB3CCB37CD4E557B2EAC9DA3C" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_508694490B19871D8C3857B2EAC809F8" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaap_PlanNameAxis_A5F636297DB5D919C78C57B2EAC8792E" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_508694490B19871D8C3857B2EAC809F8" xlink:to="loc_us-gaap_PlanNameAxis_A5F636297DB5D919C78C57B2EAC8792E" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaap_PlanNameDomain_D815CC16653452EFED0E57B2EAC87E70_default" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_A5F636297DB5D919C78C57B2EAC8792E" xlink:to="loc_us-gaap_PlanNameDomain_D815CC16653452EFED0E57B2EAC87E70_default" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaap_PlanNameDomain_D815CC16653452EFED0E57B2EAC87E70" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_A5F636297DB5D919C78C57B2EAC8792E" xlink:to="loc_us-gaap_PlanNameDomain_D815CC16653452EFED0E57B2EAC87E70" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockCompensationPlanMember" xlink:label="loc_us-gaap_StockCompensationPlanMember_766A6CF5E68885D50C1E57B2EAC87F8C" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_D815CC16653452EFED0E57B2EAC87E70" xlink:to="loc_us-gaap_StockCompensationPlanMember_766A6CF5E68885D50C1E57B2EAC87F8C" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_AnnualEquityBonusPlanMember" xlink:label="loc_afg_AnnualEquityBonusPlanMember_B10657E12C742E5D369857B2EAC87E28" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_D815CC16653452EFED0E57B2EAC87E70" xlink:to="loc_afg_AnnualEquityBonusPlanMember_B10657E12C742E5D369857B2EAC87E28" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_NetOfTaxUnrealizedGainsLossesOnCreditOnlyImpairedSecurities" xlink:label="loc_afg_NetOfTaxUnrealizedGainsLossesOnCreditOnlyImpairedSecurities_3D166F763510D9F560DF57B2EAC9D55E" xlink:type="locator" />
    <definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DA7ADF3FB3CCB37CD4E557B2EAC9DA3C" xlink:to="loc_afg_NetOfTaxUnrealizedGainsLossesOnCreditOnlyImpairedSecurities_3D166F763510D9F560DF57B2EAC9D55E" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross_DC9725A7974ADCC3E2C157B2EAC94838" xlink:type="locator" />
    <definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DA7ADF3FB3CCB37CD4E557B2EAC9DA3C" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross_DC9725A7974ADCC3E2C157B2EAC94838" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_RestrictedCommonStockIssuedFairValuePerShare" xlink:label="loc_afg_RestrictedCommonStockIssuedFairValuePerShare_DB64D1DAC29D89DE658157B2EAC90BAF" xlink:type="locator" />
    <definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DA7ADF3FB3CCB37CD4E557B2EAC9DA3C" xlink:to="loc_afg_RestrictedCommonStockIssuedFairValuePerShare_DB64D1DAC29D89DE658157B2EAC90BAF" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_F40AE1702780F7ECF50C57B2EAC98D38" xlink:type="locator" />
    <definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DA7ADF3FB3CCB37CD4E557B2EAC9DA3C" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod_F40AE1702780F7ECF50C57B2EAC98D38" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_149FC41B3965E89D565357B2EAC948B6" xlink:type="locator" />
    <definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DA7ADF3FB3CCB37CD4E557B2EAC9DA3C" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_149FC41B3965E89D565357B2EAC948B6" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_389B5549AD8D6DF1DD1E57B2EAC9581A" xlink:type="locator" />
    <definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DA7ADF3FB3CCB37CD4E557B2EAC9DA3C" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_389B5549AD8D6DF1DD1E57B2EAC9581A" xlink:type="arc" />
    <loc xlink:href="afg-20140930.xsd#afg_CommonStockIssuedDuringPeriodFairValuePerShare" xlink:label="loc_afg_CommonStockIssuedDuringPeriodFairValuePerShare_F153BC5CCFE66CB80BCF57B2EAC9435B" xlink:type="locator" />
    <definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DA7ADF3FB3CCB37CD4E557B2EAC9DA3C" xlink:to="loc_afg_CommonStockIssuedDuringPeriodFairValuePerShare_F153BC5CCFE66CB80BCF57B2EAC9435B" xlink:type="arc" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AllocatedShareBasedCompensationExpense" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_713AB07039D8592DD24757B2EAC9A2A5" xlink:type="locator" />
    <definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_DA7ADF3FB3CCB37CD4E557B2EAC9DA3C" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_713AB07039D8592DD24757B2EAC9A2A5" xlink:type="arc" />
  </definitionLink>
  <definitionLink xlink:role="http://www.afginc.com/role/ShareholdersEquityTables" xlink:type="extended" />
</linkbase>
