Why do religious organizations facilitate secular political activism in some settings and not others? This dissertation uses regional variation in political activism across Mexico to elucidate the relationship between religious organizations and political activism, as measured through associational activity and involvement in political protests. I utilize a quantitative analysis of 13,500 data observations collected from the nationally representative National Survey of Political Culture and Citizenship (ENCUP), supplemented by municipal and diocesan-level data from a variety of governmental and Church statistical databases, to test several theories describing religion's potential impact on political activism. I also utilize a qualitative comparative analysis examining the relationship between the Catholic Church and political mobilization in the Mexican States of Chiapas, Morelos, and Yucatán. I present an agent-based model developed to delineate the micro-level mechanisms linking Church institutional configurations and religion's pro-social effects to individual incentives to politically organize. The predictions of the agent-based model are assessed against my statistical dataset. The study finds where religious institutions devolve decision-making, monitoring, and sanctioning authority to the laity, individuals develop capacities to overcome collective action problems related to political activism. Religious ideology is also found to influence capacities for political activism.