What role do legacies of past mobilization under late communist rule play in the success of the radical right parties in Eastern Europe? This article considers two major legacies: the legacy of national-accommodative communism and the legacy of patrimonial communism. We investigate the effect of welfare retrenchment on vote support for radical right in 2000s. Social policy reform retrenchment in universalistic welfare systems has a highly incendiary potential for political conflict and radical parties. In countries with a legacy of national accommodative communism, early differentiation of major parties on socio-cultural issues and strategies of social policy compensation kept reform losers at bay, which limited voter success of radical parties. Highly polarized patrimonial regimes, on the contrary, are the most fertile breeding ground for the radical right due to the high levels of inequality and dissatisfaction resulting from a rapid dismantling of the welfare state. The ethnic composition of countries plays an important role in the radical right mobilization as well. Radical right parties benefit from a situation in which the titular majority faces a small ethno-cultural minority. © 2009.