Siege of Fort Watson The Siege of Fort Watson was an American Revolutionary War confrontation in South Carolina that began on April 15 , 1781 and lasted until April 23 , 1781 . Continental Army forces under Henry " Light Horse Harry " Lee and South Carolina militia under Francis Marion besieged Fort Watson , a fortified British outpost that formed part of the communication and supply chain between Charleston and other British outposts further inland . The attackers , lacking artillery , were unable to make a dent in the fortified works , and failed in attempts to deny the garrison of a water supply . They then devised a plan to build a tower from which sharpshooter s could fire into the fort ' s walls . Fort Watson was once again attacked by the Americans on April 23 , with the British forces unable to control the walls due to musket fire from the tower . They surrendered shortly afterwards . Background . Great Britain ' s " southern strategy " for winning the American Revolutionary War appeared in some ways to be going well after the Battle of Guilford Courthouse in March 1781 . General Lord Cornwallis had defeated General Nathanael Greene , but his army was short on supplies and had suffered significant casualties , so he decided to move to Wilmington , North Carolina to resupply and refit his troops . Greene , while he had lost the battlefield , still had his army intact . After shadowing Cornwallis for a time , he turned south , and embarked on an expedition to recover Patriot control of South Carolina and Georgia , where British and Loyalist forces were thinly distributed , and smaller outposts were subject to attack from larger forces under the command of Greene or one of the Patriot militia commanders in the area . He first ordered Colonel Henry " Light Horse Harry " Lee to continue shadowing Cornwallis so that his southward movement was screened . Once he was on his way into South Carolina , he ordered Lee to abandon Cornwallis and instead join forces with militia Colonel Francis Marion in the eastern part of the state . Lee and Marion met on April 14 , and first targeted Fort Watson , a small stockade d fort on the east side of the Santee River . Siege . John Watson , the commander of the fort , had gone to Lord Rawdon at Camden , and left Lieutenant James McKay in command of 120 men . When Marion and Lee first approached the fort on April 16 , their thought was to cut off the fort ' s water supply , as there was no decent cover near the fort for attack or sniping . While they successfully denied the fort access to the nearby lake , the garrison dug a well , frustrating that plan . One of Gen . Marion ' s subordinates , Major Hezekiah Maham , then came up with the idea of building a log tower of green pine with sufficient height and thickness to allow protected sharpshooters in the nest up top to fire into the fort . After several days ' preparation off - site , the approximately tower was brought within effective firing range and erected on the night of April 22 . The next day the Americans attacked , with riflemen shooting into the fort , forcing the defenders off the walls . Simultaneously , two forlorn hope parties attacked and successfully scaled them , forcing the surrender of the garrison shortly thereafter . Aftermath . The victory broke one link in the chain of communications and supply outposts between Charleston and Camden . Lee and Marion next chased after Watson , to whom Rawdon had given 500 men and the task of chasing down Marion , at least until it became known that Lee had joined with Marion , turning the tables . Since Greene ' s destination was Camden , he wanted to prevent Watson from rejoining Rawdon before he got there . In this Lee and Marion were successful ; Rawdon , concerned about his supply line , battled Greene at Hobkirk ' s Hill north of Camden without the benefit of Watson ' s men . Rawdon , although he won the battlefield , later withdrew to Charleston . Legacy . The remarkable success of the " Maham Tower " resulted in its being employed in a number of subsequent actions , most notably at the Siege of Ninety Six the following month . The fort ' s site , which is also the site of a Santee Indian burial mound , is a historic site in Clarendon County , South Carolina .