Authorized June 6, 1775 in the South Carolina State Troops as the South Carolina Regiment of Horse Rangers. Organized in summer 1775 at Ninety-Six Courthouse to consist of nine companies from western South Carolina. Redesignated November 12, 1775 as the 3rd South Carolina Regiment. Adopted July 24, 1776 into the Continental Army and assigned to the Southern Department. Captain Ezekiel Polk's Independent Company (organized in summer 1775 in western South Carolina) concurrently redesignated as the 10th Company, 3rd South Carolina Regiment.

Assigned November 23, 1776 to the 1st South Carolina Brigade, an element of the Southern Department. Relieved August 26, 1778 from the 1st South Carolina Brigade and assigned to the 2nd South Carolina Brigade, an element of the Southern Department. Relieved January 3, 1779 from the 2nd South Carolina Brigade.

Assigned February 1, 1779 to the South Carolina Brigade, an element of the Southern Department. Reorganized February 11, 1780 to consist of nine companies. Captured May 12, 1780 at Charleston by the British Army. Disbanded January 1, 1781.

Engagements:

Charleston 1775-1776
Southern Highlands
Savannah
Charleston 1780

Detachments additionally served in the following:

Cherokees 1776
Florida 1778

The regiment was established by the South Carolina Provincial Congress in June 1775 as mounted riflemen who used horses for transportation but dismounted to fight on foot. It consisted of a lieutenant colonel commandant, a major, nine captains, eighteen lieutenants, a surgeon, a paymaster, an adjutant, and a quartermaster, and with each of its nine companies having two sergeants, a drummer, and fifty privates. The regiment was placed on the Continental Establishment in September 1776 as mounted riflemen, and in October its complement increased to 600 men in twelve companies, with the commanding officer, the major, and the senior captain, all being promoted one grade.

The regiment was recruited in the backcountry and on the frontiers, and normally served in multi-company detachments, one of which took over Fort Charlotte in July 1775. Another detachment was bloodied in the fighting at Ninety Six in November 1775 and in the "Snow Campaign," which followed.

In June 1776, the whole regiment defended the eastern end of Sullivan's Island when the British attempted an amphibious assault during the naval attack on the fort, which was later named Fort Moultrie.