How French and American colonizers created systems of enslavement in the Middle Mississippi Valley The Centrality of Slavery examines how French and American colonizers used the powers of various imperial regimes to create slave societies in present-day Missouri and Illinois from the 1720s through the 1820s. The first book-length study of slavery and empire in both Illinois and Missouri, it begins with the origins of Native American and African American enslavement in the region. It then traces how successive French, Spanish, British, and American regimes shaped the development of slavery over the course of a century, examines the significance of the Northwest Ordinance's ban on slavery in Illinois, and then analyzes the diverging histories of slavery in Illinois and Missouri in the early 1800s. The book concludes with an analysis of the Missouri Crisis and the compromise of 1820, along with the Middle Mississippi Valley's significance in the road towards disunion and civil war in the late 1850s. More broadly, The Centrality of Slavery argues that the Middle Mississippi Valley sat astride the crossroads of imperial North America. The practices of empire and enslavement forged and fought over there exerted an outsized influence on the history of slavery in North America and the United States. Rather than treating the region's eighteenth-century past as a prologue to the rise of the United States, John Craig Hammond analyzes the colonial history of the region on its own terms, through the European colonizers, American settlers, and enslaved people of Indigenous and African descent who shaped the development of slavery in the Middle Mississippi Valley.