The standard narrative of American religious history largely omits the story of religion and the American West. Integrating this story would produce a more coherent history of American religion, allowing nuanced consideration of interactions between Native Americans and colonists and eliminating gaps in the traditional narrative. The West serves as a microcosm and predictor of national religious developments and also contributes to the study of world religions. Five themes have emerged in recent scholarship on religion and the American West: race and ethnicity; transnationalism; the construction of the category of religion; religion and the environment; and the myth of the American West. Scholars in the field face four challenges: learning from Western history’s definitional debates and defining the boundaries of religion and the American West; showing that the American West is a useful unit of regional analysis; constructing synthetic narratives of religion and the American West; and integrating the story of religion and the American West into the story of American religion as a whole.