The mental representations and behaviors we commonly call “religious”—everyday supernatural imagination, tribal cults, archaic religions, modern world religions—are amenable to explanation both in terms of computational, information-processing systems and in terms of adaptations that emerged during human evolution. These two research programs, focused on proximate and ultimate aspects of cultural representations respectively, have been particularly fruitful in the last 30 years. Early developments in cognitive approaches ushered in a whole new field in the study of religion. More recently, evolutionary psychology has provided new tools for explaining the emergence and transmission of religious ideas. This chapter aims to show how this cognitive and evolutionary approach can provide a better understanding of the historical diversity of religious systems.