AbstractThis article examines the politics of music at the Carlisle Indian Industrial School, the flagship federal off-reservation boarding school for the compulsory education of Indigenous children, established in Carlisle, Pennsylvania, in 1879. By examining the music education and performance culture at the Carlisle School, this article considers the role of music both within boarding school discourses of “civilization” and in terms of the larger federal goal of dispossession of Native land. Based on original archival research and engagements with contemporary discourses in Indigenous music and sound studies, the article then considers a nationalistic comic opera titled The Captain of Plymouth performed by Native students at the Carlisle commencement exercises in 1909. It argues ultimately that, although music, dance, and expressive culture were a central concern for federal assimilationist policy, music making at Carlisle provided a groundwork for the emergence of an intertribal social formation that guided musical practices and self-determination movements of the twentieth and twenty-first centuries.