... Charleston became more prosperous in the plantation-dominated economy of the post-Revolutionary years. The invention of the cotton gin in 1793 revolutionized this crop's production, and it quickly became South Carolina's major export. Cotton plantations relied heavily on slave labor. Slaves were also the primary labor force within the city, working as domestics, artisans, market workers or laborers. Many black Charlestonians spoke Gullah, a language based on African American structures which combined African, French, German, Jamaican, English, Bahamian and Dutch words. In 1807 the Charleston Market was founded. It soon became a hub for the African-American community, with many slaves and free people of color staffing stalls.