In an era of increasing autocratisation worldwide, political diaspora groups play a crucial role in supporting democratic opposition in their home countries. This project examines how political opportunities and constraints in democratic receiving countries shape the mobilization strategies of political diaspora groups, with a specific focus on Russian political exiles in Germany, Lithuania, and Sweden. Democratic countries of the Baltic Sea region have become key destinations for opposition groups fleeing from illiberal or autocratic regimes in Eastern Europe, yet diaspora mobilization is profoundly affected by these receiving states’ geopolitical interests and their relations with allies or the exiles’ home countries. The project will provide a systematic understanding of the factors that facilitate or hinder diaspora activism and explore how differences between receiving countries’ political opportunity structures facilitates some diaspora groups’ mobilisation while obstructing others. By employing a mixed-methods approach, combining qualitative case studies with quantitative approaches such as protest event analysis and organisational surveys, the activism of Russian political exiles will be compared with how other groups and actors in civil society respond to Russian aggression and autocratisation. The project will gain new insights into the conditions for political diaspora activism in democracies during a period of growing authoritarianism and geopolitical tensions.