The Imperial Gridiron examines the competing versions of manhood at the Carlisle Indian Industrial School between 1879 and 1918. Students often arrived at Carlisle already engrained with Indigenous ideals of masculinity. On many occasions these ideals would come into conflict with the models of manhood created by the school’s original superintendent, Richard Henry Pratt. Pratt believed that Native Americans required the “embrace of civilization,” and he emphasized the qualities of self-control, Christian ethics, and retaliatory masculinity. He encouraged sportsmanship and fair play over victory. Pratt’s successors, however, adopted a different approach, and victory was enshrined as the main objective of Carlisle sports. As major stars like Jim Thorpe and Lewis Tewanima came to the fore, this change in approach created a conflict over manhood within the school: should the competitive athletic model be promoted, or should Carlisle focus on the more self-controlled, Christian ideal as promoted by the school’s Young Men’s Christian Association? The answer came from the 1914 congressional investigation of Carlisle. After this grueling investigation, Carlisle’s model of manhood starkly reverted to the form of the Pratt years, and by the time the school closed in 1918, the school’s standards of masculinity had come full circle.