Siege of Charleston The Battle of Charleston was one of the major battles which took place towards the end of the American Revolutionary War , after the British began to shift their strategic focus towards the American Southern Colonies . After about six weeks of siege , Continental Army Major General Benjamin Lincoln surrendered forces numbering about 5 , 000 to the British . Background . In late 1779 , following strategic failures earlier in the war , the British were stymied by the waiting strategy adopted by General George Washington leading the Continental Army . Under political pressure to deliver victory , British leaders turned to launching their " southern strategy " for winning the war , that built on the idea that there was strong Loyalist sentiment supporting the southern colonies . Their opening move was the Capture of Savannah , Georgia in December 1778 . After repulsing a siege and assault on Savannah by a combined Franco - American force in October 1779 , the British planned an attack on Charleston , South Carolina which they intended to use as a base for further operations in the north . Siege . The British government instructed Sir Henry Clinton to head a combined military and naval expedition southward . He evacuated Newport , Rhode Island , on October 25 , 1779 , and left New York City in command of Hessian General Wilhelm von Knyphausen . In December , he sailed with 8 , 500 troops to join Colonel Mark Prevost at Savannah . Charles Cornwallis accompanied him , and later Lord Rawdon joined him with an additional force , raising the size of the expedition to around 14 , 000 troops and 90 ships . Marching upon Charleston via James Island , Clinton cut off the city from relief , and began a siege on April 1 . Skirmishes at Monck ' s Corner and Lenud ' s Ferry in April and early May scattered troops on the outskirts of the siege area . Benjamin Lincoln held a council of war , and was advised by de Laumoy to surrender given the inadequate fortifications . Clinton compelled Lincoln to surrender on May 12 . The loss of the city and its 5 , 000 troops was a serious blow to the American cause . It was the largest surrender of an American armed force until the 1862 surrender of Union forces at Harper ' s Ferry during the Antietam Campaign . The last remaining Continental Army troops were driven from South Carolina consequent to the May 29 Battle of Waxhaws . General Clinton returned to New York City in June , leaving Cornwallis in command with instructions to also reduce North Carolina . Aftermath . In his book " A history of the campaigns of 1780 and 1781 " , Banastre Tarleton reported a total of 5 , 283 captured , including three signers of the Declaration of Independence : Edward Rutledge , Arthur Middleton and Thomas Heyward , Jr . An active and bitter partisan war began . The British advance was marked by more than the usual destruction of war ; the Loyalists rose to arms ; the Patriot population regrouped around some of its militia commanders to harass the British and their Loyalist allies . Little mercy was shown on either side , especially after Tarleton ' s decimation of the Continentals at the Battle of Waxhaws and Light Horse Harry Lee ' s decimation of the Loyalists at Haw River , which many saw as massacres . Charleston remained under British control until they evacuated it in 1782 due to the imminent Treaty of Paris . Orders of battle . British Forces : Colonial Forces : Three current Army National Guard units ( 116th Inf , 263rd ADA and 131st MP Co are derived from American units that participated in the Siege of Charleston . There are only thirty Army National Guard and active Regular Army units with lineages that go back to the colonial era .