A groundbreaking study situating the Mississippi River valley at the heart of the early American republic’s political economy Shortly after the ratification of the US Constitution in 1789, twenty-two-year-old Andrew Jackson pledged his allegiance to the king of Spain. Prior to the Louisiana Purchase, imperial control of the North American continent remained an open question. Spain controlled the Mississippi River, closing it to American trade in 1784, and western men on the make like Jackson had to navigate the overlapping economic and political forces at work with ruthless pragmatism. In Empire of Commerce, Susan Gaunt Stearns takes readers back to a time when there was nothing inevitable about the United States’ untrammeled westward expansion. Her work demonstrates the centrality of trade on and along the Mississippi River to the complex development of the political and economic structures that shaped the nascent American republic. Stearns’s perspective-shifting book reconfigures our understanding of key postrevolutionary moments—the writing of the Constitution, the outbreak of the Whiskey Rebellion, and the Louisiana Purchase—and demonstrates how the transatlantic cotton trade finally set the stage for transforming an imagined west into something real.