Can External Threats Foster a European Union Identity? Evidence from Russia’s Invasion of Ukraine

Abstract Can external threats strengthen group identity? A growing body of research in economics emphasises the importance of cultural attributes such as identity for trust and cooperation. However, where these attributes come from is not well understood. This paper examines reactions to the Russian invasion of Ukraine in 2014, looking at European Union member states. Comparing low-threat to high-threat states in a difference-in-differences design, I find a sizeable and persistent positive effect on EU identity. It is associated with higher trust in EU institutions and support for common policies. Lower-level identities remain unaffected, and proximity to Russia and Russian minority size are driving high-threat status.