Regionally-based nationalist parties and movements are a normal part of political processes throughout the world. Separatist parties function within the normal political and governmental process, and often are even part of the national government. At times, however, the separatist goal surfaces in an overt effort to secede. What fuels the secessionist moment in a country? We examine this question from the perspective of the voters. When a region seeks to leave a nation, what ideas or values are activated within that region that increase public support for secessionist parties and leaders? We show, through a careful, analytical comparison of the Catalan and Basque regions since 2000, that the secessionist efforts in Catalonia have been reflected as a rise in language-based identity politics. In this regard, we find strong evidence supporting a wider set of scholarship that argues that secession and separatism is rooted in identity politics, rather than economic interests or political ideologies.