Slave Trader, Sold to Tennessee, a watercolor sketch by the artist Lewis Miller from the mid-1850s. Miller depicts a group of slaves being marched from Virginia to Tennessee. Once Congress voted to prohibit the further importation of slaves into the country, slaveowners in newly opened areas of the country had to obtain slaves from other parts of the United States.
Historians estimate that around 1 million slaves were shifted from the older slave states to the Deep South between 1800 and 1860. Some traveled with their owners to newly established plantations, but the majority were transported by slave traders to be sold at auction for work in the cotton fields. Slave trading became a well-organized business, with firms gathering slaves in Maryland, Virginia, and South Carolina and shipping them to markets in Mobile, Natchez, and New Orleans. Slave coffles—groups chained to one another on forced marches to the Deep South—became a common sight. A British visitor to the United States in the 1840s encountered what he called a “disgusting and hideous spectacle,” a file of “about two hundred slaves, manacled and chained together,” being marched from Virginia to Louisiana. A source of greater freedom for many whites, the westward movement meant to African-Americans the destruction of family ties, the breakup of longstanding communities, and receding opportunities for liberty.
In 1793, when Whitney designed his invention, the United States produced 5 million pounds of cotton. By 1820, the crop had grown to nearly 170 million pounds. Thomas Jefferson had believed that European demand for American grain would underpin the nation’s economic growth and the small farmer’s independence. But as the southern economy expanded westward, it was cotton produced on slave plantations, not grain grown by sturdy yeomen, that became the linchpin of southern development and by far the most important export of the empire of liberty.