The rise of populist parties in Europe has generated an enormous amount of academic literature. Previous research has thoroughly examined the factors contributing to the electoral success of populist parties. Surprisingly, very little attention has been paid to the role of decentralization, one of the most widespread forms of governance in the world. This paper aims to fill this gap by presenting a theoretical and empirical account of the effect of decentralization on the electoral fortunes of populist parties in Europe. Using aggregated data from election results in 30 European countries, this paper puts competing hypotheses to the test. I argue that the mechanism linking decentralization and populist parties’ national election results is, in fact, indirect and depends on the existence of a regional tier of government. Results suggest that having representation in subnational parliaments plays a significant role in the national success of populist parties, and this effect is contingent on the degree of regional authority.
