Even though General Nathaniel Greene's army suffered a defeat at the hands of General Cornwallis at the Battle of Guilford Courthouse, Greene's army was largely still intact. Cornwallis moved his army to Wilmington, North Carolina, and Gen. Greene took advantage of this move by marching his forces into South Carolina, to begin the process of driving out the British.
On May 22, 1781, Greene began siege operations against the British "Star Fort" in Ninety Six. The Siege of Ninety Six was the longest siege during the war, lasting 28 days. With a failed assault by Greene's forces, and with British reinforcements on the way, Greene ordered a retreat and headed back to Charlotte, North Carolina. Ninety Six was a victory for the British.