Indigenous Sacraments provides the first study of Indigenous perceptions of the Christian sacraments at the fringes of colonial Spanish America, particularly in the missions established by the Jesuits in northwestern Mexico, central southern Chile, and the Gran Chaco. After Jesuit missionaries arrived in these regions between the end of the sixteenth and the early seventeenth centuries, their sacraments came to control every rite of passage, from birth to reaching adulthood to the formation of new families to death. Through the administration of the sacraments, missionaries intended to replace extant Indigenous habits and beliefs with Christian values. The disruptions triggered by such processes raised multiple local reactions, from initial curiosity and incomprehension to rejection, partial acceptance, and ritual imitation. Locals debated the newly introduced rituals and both violently rejected them and developed their own versions, becoming active participants in the sacraments’ diffusion. Oriol Ambrogio Gali draws on a range of diverse sources to explore the changing attitudes toward the sacraments and to highlight the cultural and religious evolution of the Indigenous groups living at the fringes of Spanish America. By exploring local perceptions of the Christian sacraments, Ambrogio Gali shows that Indigenous peoples were far from static recipients of Christianity in the Americas.