This chapter analyzes how the distinctive institutional environments and their corollary ramifications on religious authority drive religious movements to adopt different strategies in shaping their political activism and creating religious parties, focusing on religious competition and conflict. Islamist movements, unperturbed by a hierarchical religious authority, found the liberty to pursue hybrid organizational structures. This carte blanche to assume religious authority enabled Islamist movements to operate both as a religious movement that serves in religious, social, and educational areas and as a religious party in the political arena. The Church hierarchy, by contrast, forced Catholic mass movement leaders to choose between expulsion and avoiding political activism in the name of Catholicism. Catholic political activists largely responded to this challenge by formally parting ways with mass movements and creating their own Catholic parties without the Church's blessing, ultimately deprived of the ability to rely on religious authority in their political ventures. In addition, this chapter focuses on the implications of distinct organizational trajectories on the electorate.

The politicization of religion and emergence of a religious political identity in the modern era is firmly anchored in the rise of mass religious movements – a hitherto unknown phenomenon. These movements became the main instruments for fulfilling the newly developed religious sociopolitical vision. Not only did they play a crucial role in raising a religious generation to confront social change and secularization, but they also aimed to confront deviant ideologies and remake the political system in line with their religious visions. In this distinctly political objective lie the seeds of religious political parties, which carry the missions of religious mass movements into the political arena. Religious movements embody the ideal organizational form of modern religiopolitical activism – they can lay out a vision for societal and political transformation, teach and preach this vision, and mobilize resources and communities to achieve it. These movements translated the bourgeoning religious responses to modernization and secularization into tangible social, religious, and political agendas. This chapter analyzes the emergence of mass religious movements in the Middle East and Western Europe.