Western scholarship has underlined the relevance of social identity, perceived efficacy, emotions, and cost–benefit assessments as central catalysts of collective action. Little has been done to understand the context-sensitivity of these catalysts by means of cross-culturally comparative designs. The current study explores their context-sensitivity. It aims to find out whether existing opportunity structures in a democratic, nonrepressive country like Germany produce catalysts of collective action different from those produced in an autocratic, repressive country like Turkey. It also aims to understand the role of social media in mobilizing people in these two contexts. Semistandardized interviews with activists were carried out in both co...