<i>Xs we share</i> : Context similarity, culture, and the diffusion of populism

Abstract Do populist ideas travel across borders? Anecdotal evidence suggests as much, yet so far we lack a systematic assessment of whether diffusion takes place, and if so under which conditions. We argue that context similarity enables the diffusion of populism among parties as it eases the adaption of populist framing of perceived grievances into the local context. Using a dyadic approach, we analyze diffusion effects among 923 parties in 67 countries from 1970 to 2018. We find that similar levels of political and economic exclusion foster learning from and emulating other parties abroad. We also uncover conditional effects for learning from other parties facing similar levels of income inequality or public sector corruption that hinge on a cultural prescreening. Combined, our results have important implications for a better understanding of diffusion processes in general and the spread of populist ideas around the globe in particular.