Although the literature on religious violence is contested to such a degree that one is uncertain what to call the field of study, this chapter argues that there is such a thing as religion and that under certain circumstances religions incite or legitimate deadly violence. Yet the relationship between religions, religious actors, and violence is much more complex than that. This chapter surveys the main trends of a vast literature on that relationship and sorts it into three categories and several sub-categories. Each category explicates a different conceptualization and evaluation of religion and religious agency. In the concluding section this chapter suggests that sufficient work of high quality exists to make possible the integration of the seminal insights of these literatures into a coherent theory of religion and violence.