West of Slavery: The Southern Dream of a Transcontinental Empire

When American slaveholders looked west in the mid-nineteenth century, they saw an empire unfolding before them. They pursued that vision through diplomacy, migration, and armed conquest. By the late 1850s, slaveholders and their allies had transformed the southwestern quarter of the nation – California, New Mexico, Arizona, and parts of Utah – into a political client of the plantation states. Across this vast swath of the map, white southerners defended the institution of African American c...