“Louisiana Purchases” challenges the common reduction of the US-Indian treaty system to a cycle of conquest, spinning vaguely in the background of national narratives, by calling attention to a remarkable fact dug out of a century of federal budgets: between 1790 and 1890, about 12 cents of every dollar spent by the federal government went into the conquest of Indian country. Simply put, Indian dispossession by treaty was one of the most expensive and complex functions assumed by the young United States. This dissertation follows the money to the antebellum period, when civil expenditures on the Indian treaty system peaked, to recover the story of the St. Louis Superintendency, an arm of the Indian Office whose operations transformed the Missouri River Valley in the early decades of the nineteenth century. The project traces the history of the St. Louis Superintendency from the Louisiana Purchase of 1803 through the era of Indian removal in the mid-1840s.

The St. Louis Superintendency was the largest and longest lived of thirty-five Indian superintendencies that blanketed US territories between the 1780s and 1870s. Erected to implement trade and treaty relations across a shifting Indian boundary, these organizations managed clusters of agencies, regulated trade, negotiated cessions, distributed annuities, kept accounts, and mediated between Indians, agents, and squatters. In short, they stewarded territorial expansion on the ground, and at unprecedented rates. Since the onset of North American colonization, Indians lost 98% of their land in what is now the continental United States. About 70% of those losses happened in the ninety years after the Revolution, filtered through superintendencies whose operations have escaped scrutiny because historians have approached Indian treaties as a political anomaly.

As the first sustained study of an Indian superintendency, “Louisiana Purchases” argues that federally administered Indian dispossession was instrumental to the formation of the United States, not just its tragic consequence. Created in the wake of the Louisiana Purchase, the St. Louis Superintendency ushered millions of acres of Indian Country into the public domain before closing. By combining archival work with spatial analysis in GIS, this dissertation tracks how the pace, location, and interpretation of treaty provisions structured a shifting landscape of settler colonial opportunity, at a time when the emigrant population in the Missouri River Valley exploded by more than 5,000%. The results show that the dual trajectories of indigenous dispossession and settler expansion did not simply run parallel, they spiraled together.

“Louisiana Purchases” advances recent scholarship on settler colonialism and the early national state by excavating a story that has been hidden in plain sight. Given the St. Louis Superintendency’s obscurity, most readers will be surprised to learn of its role in a series of textbook events tracked in the dissertation’s chapters. After reassessing the long-term price of the Louisiana Purchase to account for the acquisition of Indian title, these chapters follow the legal incorporation of the Louisiana Territory into the United States, the Lewis and Clark expedition, the Missouri Compromise, and Indian Removal. All of these events involved and were shaped by imperatives of Indian relations in general and the operations of the St. Louis Superintendency in particular. This dissertation excavates these connections to show that American expansion into the Missouri River Valley in the early American republic would not have looked the same without the actions of the St. Louis Superintendency.