Siege of Augusta The Siege of Augusta began on May 22 , 1781 and was conducted by General Andrew Pickens and Colonel Henry " Light Horse Harry " Lee against British troops occupying the town of Augusta , Georgia . Fort Cornwallis , the primary defenses , were successfully exposed to cannon fire by the construction of a tower high on which the Americans mounted a small cannon . The garrison surrendered on June 6 . Siege begins . On April 16 , Patriot militia companies under the command of Micajah Williamson arrived on the outskirts of Augusta , Georgia and established a fortified camp . The garrison of the town ' s primary fortification , Fort Cornwallis , was commanded by Loyalist Thomas Brown , and did not immediately confront Williamson due to exaggerated reports of his troop strength . General Andrew Pickens maneuvered a force of 400 men between Augusta and Ninety Six , South Carolina to prevent the British outpost there from reinforcing Brown . On May 15 , Williamson was joined by his commander , Elijah Clarke and another 100 men , effectively cutting British supply lines . General Nathanael Greene had sent Major Henry Lee to attempt the capture of Ninety Six , but when Lee neared he learned that the town had been fortified in anticipation of Greene ' s arrival . Greene then ordered Lee to assist Pickens at Augusta . Pressing on Lee reached Augusta after traveling in three days . Galphin ' s prize . On May 21 , the stockaded house of George Galphin , an Indian agent , located south of Augusta , was attacked by forces under Clarke and Lee . After a brief exchange , in which one Patriot died of the heat and eight to ten were wounded , the British garrison there surrendered after three or four men were killed . A total of 126 men , mostly regulars , surrendered . The prize ( and the reason for the Patriot attack ) was much - needed supplies and military equipment which had been intended for distribution to the local Indians . Fort Grierson . Fort Grierson was a secondary fortified outpost located about half a mile ( 0 . 8 km ) from Fort Cornwallis . This fort was defended by about 80 men under Colonel Grierson . On May 23 the Patriot forces began to encircle the fort in a manner intended to draw Grierson out in an attempt to reach Fort Cornwallis . Brown , aware of the danger to Grierson , sallied forth from Cornwallis , but when faced with Lee ' s strength , limited his support attempt to an ineffective cannonade . Grierson , desperate to escape the trap , attempted to flee along the riverbank but his entire company was captured . Clarke ' s men then took their revenge on similar actions perpetrated by Brown , and refused quarter , killing Grierson and all of his men . Fort Cornwallis . The forces defending Cornwallis numbered about 300 Loyalist militia , who were assisted in defensive works by about 200 African - Americans . The fort was well - constructed and the Patriots could not find a ready means of attack , since they only had a single cannon . At Lee ' s suggestion they decided to use a stratagem that had met with success at the Siege of Fort Watson . Under cover of a nearby house , they constructed a wooden tower about high . During its construction Brown made several further sortie s , but Lee ' s men fought them off each time . The tower was high enough to top the fort ' s walls on June 1 and the Patriots began firing into the fort . That night Brown led most of the garrison out and a pitched battle ensued in which Brown was once again forced to retreat behind his defenses . He then sent out one of his men , pretending to be a deserter , to gain access to the tower with a view to setting it on fire . He suggested to Lee that he could direct the cannon at the fort ' s magazine , and had very nearly succeeded in his quest when Lee somehow became suspicious and had him placed under guard . The cannon atop the tower continued to rake the interior of the fort , knocking guns off their mounts and destroying the barracks . The Patriot leaders then began planning an attack on the fort , exploring places to position sharpshooters in the few remaining houses near the fort . On the night of June 3 the last remaining house exploded . Brown had sent sapper s to undermine the house , expecting it to be used for such purposes , and the explosive charge had gone off before the building was occupied . Patriot forces lined up for assault on the morning of June 4 , and Pickens and Lee sent in a surrender demand , which Brown turned down . In deference to the fact that it was the King ' s birthday , the attack was delayed one day . Surrender . On June 5 , Brown offered to negotiate terms of surrender . To avoid a repeat of Grierson ' s fate , he was specifically surrendered to a detachment of Continental Army troops from North Carolina , as a number of the local militia were interested in seeing him dead over his previous acts of brutality . Aftermath . Brown survived the war , moving first to Florida and then the Bahamas .