This paper addresses a gap in the current literature on secessionism by shedding light on the often-overlooked impact of event-driven instances of 'lost autonomy' in fueling secessionist movements. While the influence of lost autonomy on secessionism is widely acknowledged, existing literature tends to approach it from a rather static perspective, conceptualizing and operationalizing lost autonomy as a process-like phenomenon. Our argument posits that the (perception of) loss of autonomy often crystallizes in a singular event, a 'lost autonomy trigger,' which causally precipitates secessionist action. This study analyzes the causal effects of two events commonly identified as lost autonomy triggers for secessionist waves - the Bank crises on the Faroe Islands in 1992 and the Court Ruling in Catalonia in 2010. Employing a mixed-methods approach, we integrate qualitative process tracing with a synthetic control method, utilizing novel data on vote shares of secessionist parties in 13 minority regions in Europe. By emphasizing the dynamic nature of lost autonomy triggers and their impact on secessionist collective action, we contribute to a more nuanced understanding of the dynamics underlying secessionism.
