This thesis is a comparative study of young people’s experiences at the Carlisle Indian Industrial School (CIIS) and the Pennsylvania Reform School, also known as Morganza, in the late 19th and early 20th centuries. Emancipation, immigration, and the military conquest of Native nations across the trans-Mississippi West radically altered the United States’ body politic and territorial extremities, sparking white Protestant middle- and upper-class anxieties about others’ movement, respectability, and belonging. Native, Black, and white ethnic youth, all defined as culturally different but perceived as malleable enough to be redeemed on account of their age, were funneled into assimilative and carceral institutions such as Carlisle and Morganza, where they would be isolated from outside influences for their “uplift.” Assimilation would have dramatically different objectives and outcomes for each group based on their structural position in American empire; however, its procedural violence against youth was widespread. While attempting to effect their own release, young people at both sites navigated harsh discipline, barriers to communication, and substandard conditions that clarified Carlisle and Morganza’s similarities and the enduring relationship between incarceration and assimilation as mechanisms for young people’s repression.