Slave Trade Ends: US Abolishes International Commerce in 1807

The United States banned the importation of enslaved people on the earliest date the Constitution allowed, and then spent the next fifty years barely enforcing the law. Congress passed the Act Prohibiting Importation of Slaves on March 2, 1807, effective January 1, 1808, closing the legal international slave trade while leaving the institution of slavery itself — and a booming domestic trade — completely intact. Article I, Section 9 of the Constitution had included a compromise with Southern slaveholders: Congress could not prohibit the importation of enslaved persons before 1808. President Thomas Jefferson, himself an enslaver, called for the ban in his December 1806 annual message to Congress, and both chambers acted quickly. The bill passed with broad support, including from some Southern representatives who recognized that ending imports would increase the value of enslaved people they already held. The law imposed penalties of forfeiture of the ship and cargo, with fines ranging from $800 to $20,000 depending on the offense. Enforcement fell to the small US Navy, which lacked the ships to patrol the vast Atlantic coastline effectively. Smuggling continued for decades, particularly through Spanish Florida and later Texas. An estimated 50,000 enslaved Africans were illegally imported after the ban took effect. Congress strengthened the law in 1819, declaring the slave trade piracy punishable by death and authorizing Navy patrols off Cuba and South America. Even so, no American was ever executed under the piracy provision. The domestic slave trade exploded in the absence of imports: more than one million enslaved people were forcibly relocated from the Upper South to the Deep South between 1810 and 1860, transported by ship, riverboat, and overland coffles. Britain had abolished its own slave trade the same year, creating a transatlantic moment of legislative action whose moral promise would take another six decades — and a civil war — to fulfill.