This dissertation focuses on army officers' efforts to both conquer American Indians and answer to competing visions of political authorities and citizens who were divided over the "Indian question." Although army officers served as representatives of federal power on the frontier, they were often limited both in their perceptions of Indians and the restrictions placed on them by federal, state, and territorial governments. The officer corps was able to use its authority and resources to advance the national goal of western settlement. However, its efforts to replace a native West with a white West were neither unified nor bereft of tension.

Indians, recognizing imbalances in power among American authorities, sought to maintain their own hegemony. With their sophisticated use of political alliances and rhetoric, they took advantage of Anglo-American misunderstandings about native people. This project treats Indians as competitors against a rival Anglo-American empire that sought to control the West. Rather than see native people as marginalized figures, I argue that the army was marginalized within the dominant civilian state. This marginalization, combined with their difficulty in responding to native sovereignty and the disunity posed by their individual interpretations of federal Indian policy, had a lasting effect on the way in which the army pursued its mission on the frontier. Territorial officials, entrepreneurs who promoted western settlement, and civilians themselves often acted in ways which hampered the army's efforts.