This Element examines the relationship between mental health and religiosity from an evolutionary perspective. Drawing on psychology, anthropology, and health science, it explores the origins of religiosity and the cultural evolution of religious traditions to identify how religious beliefs, behaviors, and affiliations have influenced human psychosocial functioning over time. First, it defines the concepts of mental health and religiosity and then summarizes research on contemporary associations between them. This synthesis highlights the multidimensionality of each construct and the variability in their association across individuals and cultural contexts. Building on theory, the Element introduces a novel multilevel framework to explain how religiosity and mental health have interacted differently across evolutionary, cultural, and personal timescales. It concludes by considering applications of this evolutionary science, proposing that individuals who understand how religiosity and mental health are associated can more intentionally cultivate personal forms of religiosity that benefit, rather than hinder, well-being.
