Publication Type: Conference Paper/Unpublished Manuscript Review Method: Peer Reviewed Abstract: Distinctions between core polity and territorial periphery point to an important spatial dimension in the exercise of federal governing authority. In the core polity, the Constitution divided governing authority between the federal government and the states. At the periphery, the federal government exercised broad powers outside of the limitations that federalism imposed on federal governing authority. Extensive authority and the need for government institutions made the territorial periphery a central site for 19th century federal state-building. After exploring the historical roots of federal authority over the territorial periphery, the article discusses the role of the U.S. Army, the Indian office and the General Land Office in the establishment of governing authority in U.S. territories during the antebellum republic. A territorial analysis of federal state-building during the 19th century revises prevalent conceptions of the 19th century American state. While federal authority was restrained in the core polity, sweeping federal authority and the need for the establishment and enforcement of governing institutions made the territorial periphery a major site of federal state-building. A revised account of 19th century federal state-building acknowledges the weaknesses of the federal government at the core and emphasizes its strengths at the periphery.