Fort Pemberton, a large five-sided Confederate earthwork on the James Island side of the Stono River, was one of the largest forts constructed by Confederate authorities for the defense of Charleston. Construction on the pentagonal earthwork was initiated in 1861 by the order of Confederate Commander Brigadier General John C. Pemberton for which the fort is named.

Completed in 1862, the fort was 400 feet by 350 feet with an additional rampart 700 feet long. The earthen walls are 10 to 12 feet high and 20 feet wide at the base. The fort was initially armed with twenty guns of various calibers and built to keep Union gunboats from approaching Charleston from the Stono River. Fort Pemberton also included two powder magazines and a hot-shot furnace. Some of the fort’s guns faced inland to defend a land assault as well. Once Battery Tynes and Pringle were constructed downstream in 1863, Fort Pemberton was of less strategic importance.

In June 1864, Fort Pemberton was manned by Company B, 15th Battalion, South Carolina Heavy Artillery, commanded by Captain Guignard Richardson. Its armament at that time was two 32-pounder banded rifled guns and two 32-pounder smoothbore cannon. The fort was described in February 1865 by Union troops as “a large well-built work, heavily armed.” Fort Pemberton and the rest of Charleston’s defenses were evacuated on February 17, 1865.