When Andrew Jackson’s removal policy failed to solve the “Indian problem,” the federal government turned to religion for assistance. Nineteenth-century Catholic and Protestant reformers eagerly founded reservation missions and boarding schools, hoping to “civilize and Christianize” their supposedly savage charges. In telling the story of the Saint Francis Indian Mission on the Sicangu Lakota Rosebud Reservation, Converting the Rosebud illuminates the complexities of federal Indian reform, Catholic mission policy, and pre- and post-reservation Lakota culture. Author Harvey Markowitz frames the history of the Saint Francis Mission within a broader narrative of the battles waged on a national level between the Catholic Church and the Protestant organizations that often opposed its agenda for American Indian conversion and education. He then juxtaposes these battles with the federal government’s relentless attempts to conquer and colonize the Lakota tribes through warfare and diplomacy, culminating in the transformation of the Sicangu Lakotas from a sovereign people into wards of the government designated as the Rosebud Sioux. Markowitz follows the unpredictable twists in the relationships between the Jesuit priests and Franciscan sisters stationed at Saint Francis and their two missionary partners—the United States Indian Office, whose assimilationist goals the missionaries fully shared, and the Sicangus themselves, who selectively adopted and adapted those elements of Catholicism and Euro-American culture that they found meaningful and useful. Tracing the mission from its 1886 founding in present-day South Dakota to the 1916 fire that reduced it to ashes, Converting the Rosebud unveils the complex church-state network that guided conversion efforts on the Rosebud Reservation. Markowitz also reveals the extent to which the Sicangus responded to those efforts—and, in doing so, created a distinct understanding of Catholicism centered on traditional Lakota concepts of sacred power.