The introduction discusses the problem of the study of modern religion and race, particularly as they are reflected in the concept and categories of religion and the secular. A review of recent debates about secularism and the secular points to the general absence of an examination of religion’s (as well as the secular’s) imbrication with colonialism and race. The chapter provides a comprehensive introduction to decolonial thought by reviewing its theoretical background, central claims, key figures, topics, and questions. On the one hand, decolonial theory reveals the colonial edifice of secularity. On the other hand, the leading conversations in decolonial theory tend to take the concept of religion for granted, thus reproducing secularist categories and frameworks.