In the Spring of 1780 the British Army under Sir Henry Clinton decided that Savannah, then in British hands, was inconvenient as a port to support the planned British conquest of the Carolinas. Charleston with its fine natural harbor was selected to serve as the British headquarters for the Southern colonies. Clinton landed a substantial army below Charleston and by late March had the city nearly surrounded.
Charleston was defended by a small fleet of frigates and sloops commanded by Abraham Whipple, and by about 3,500 Continental troops and militia, under the overall command of General Benjamin Lincoln. As the British consolidated their hold on the areas outside of the city, Lincoln attempted to strengthen the fortifications which protected it from direct attack. Whipple decided the small ships under his command were no match for the British fleet and withdrew them up the Ashley River.
By April, British troops under Lord Cornwallis had secured the Cooper River area east of the city, and Lincoln found his command completely surrounded. Lincoln requested to be able to surrender with the Honors of War. Clinton denied this request and tightened his grip on the surrounding area. By the beginning of May British artillery was hitting homes in the city.
On May 7 Fort Moultrie, located on Sullivan’s Island outside of the city, surrendered to the British. Civilian leaders within Charleston petitioned Lincoln to surrender to avoid destruction of the city by British artillery. On May 12 Lincoln agreed after again requesting the Honors of War and again being denied by Clinton. The surrender was the largest of American troops in the Revolutionary War.
The loss of Charleston and the more than 5,000 American troops and sailors was a severe blow to the Patriots, with the war in the North at a stalemate. The British captured the port of Charleston, more than 300 pieces of artillery, almost 50 ships and harbor craft, and tons of munitions and other military stores. The loss meant that there was no operational Patriot Army in the South and other than militia and guerrilla groups no resistance to British and Loyalist operations from Virginia to Georgia.