This chapter sketches the contours of prevailing approaches to the question of religion’s role and influence in world politics. It discusses different secularisms and how they have shaped the study of religion in world politics. These different secularisms give form to prevailing analytical approaches that assume that “religion” is something, a clearly identifiable and definable object and agent for analysis. Despite their differences, these secularist approaches all tend to result in analyses that either over- or under-emphasise religion’s significance in world politics and characterise it as either “good” or “bad”. The chapter demonstrates the consequences of these assumptions through a discussion of international relations (IR) analysis of the ongoing conflict in Ukraine.