Col. Thomas Sumter commanded a group of about 350 partisans and tried to take Fort Granby. After finding the fort too strong for his force to successfully attack, he decided to move to Orangeburg and attack this settlement. Orangeburg is on the North Edisto River, some 50 miles south of Fort Granby, and was a British post. Earlier, Lt. Col. Francis Rawdon had sent orders to the post for the soldiers to abandon it, but the garrison never received this order.
On the night of the 10th, Orangeburg was placed under siege by Sumter’s advanced forces, under Col. Wade Hampton, during the night. When by next morning Sumter with his six-pounder arrived, the garrison under loyalist Col. John Fisher surrendered by 7 am. 6 officers and 83 men (28 of them provincials), and many military stores and provisions, were captured as a result, and neither side apparently suffered any casualties. Sumter found Orangeburg well stock with supplies and after examining the fortifications wrote that he considered them extremely strong, adding that he believed the post could have put up a stout defense, had the garrison been so inclined. The prisoners were sent to Greene on May 12, but militia guards reportedly murdered a number of them along the way. After taking Orangeburg, Sumter moved up toward Ft. Motte, which he found Marion and Lee had already taken, he turned to putting loyalist in awe, and seizing horses and other means of transportation, and generally taking or moving supplies out of the region from Wassamasaw to Dorchester, and thereby hinder Rawdon's retreat. After doing this for two days he returned to Orangeburg, and following this moved back up to the Congaree.
Thomas Young:“Soon after this I joined a detachment of Whigs under Col. Brandon, and scouted through the country till we reached the siege at Fort Motte. There I remained for several days, when we joined a detachment under command of Col. Hampton, to take Orangeburg. The state troops, under Col. Hampton, outmarched us, for we had a piece of artillery to manage. We arrived the morning after them. The Tories were lodged in a brick house, and kept up a monstrous shouting and firing to very little purpose. As soon as the piece of artillery was brought to bear upon the house, a breach was made through the gable end; then another, a little lower; then about the center, and they surrendered.”