This article examines how political regimes in migrants’ origin countries influence their party identification in adopted homeland. I posit that immigrants are more likely to acquire partisanship in their host country if they came from a nonparty autocracy as opposed to a party-based autocracy or democracy. Moreover, among partisans, immigrants are less likely to identify with a left-wing party if they came from a communist regime. Finally, these effects are particularly pronounced among foreign-born individuals from highly authoritarian regimes. The analyses using Geddes, Wright, and Frantz Autocratic Regimes data along with individual-level data from the European Social Survey (ESS) 2002-2017 in 19 established democracies confirm these expectations. These findings have important implications for debates on immigrant political integration, party politics, and the prospects of electoral stability in contemporary democracies.