Greenwood County takes its name from its county seat, Greenwood. The town of Greenwood was named around 1824 for the plantation of an early resident, John McGehee. Greenwood County was formed in 1897 from parts of Abbeville and Edgefield counties, which were originally part of the old Ninety Six District. This part of the backcountry was not settled until the mid-eighteenth century
The town of Ninety Six was established as a frontier trading post around 1730, and it was the site in November 1775 of one of the first South Carolina battles of the American Revolution. In May 1781 American forces besieged the British-held Star Fort at Ninety Six for over a month but were forced to withdraw when British reinforcements approached.
The arrival of the railroad in 1852 stimulated cotton growing and textile manufacturing in this area. Local plantation owner Francis Salvador (1747-1776), who was killed fighting Cherokees during the Revolutionary War, was the first Jewish person elected to the state legislature. United States Congressman Preston Smith Brooks (1819-1857) and educator Benjamin Mays (1894-1984) were also residents of Greenwood County.