Rear Adm. John A. Dahlgren
Fort Sumter, 1,390 yards distant from Battery Gregg, prepared for siege, too. Brick and stone masonry “counter-forts,” already built at each extremity of the esplanade as protection for the magazines, were now strengthened, and much of the remaining gorge exterior was sandbagged or otherwise protected. The casemates on the right or sea front flank were filled with sand, and the rooms on the gorge were filled with damp cotton bales laid in sand. The upper-tier magazines were abandoned and filled with sandbags to protect the magazines below. Protective revetments and other defensive devices were introduced at various points throughout the fort. Frequently during this period the garrison was host to officers on leave, citizens of Charleston, and even many ladies, who came to see the scars of the April battle, to admire the drill, or to observe the preparations. At the end of June 1863, Fort Sumter was garrisoned by five companies (perhaps 500 men) of the First South Carolina Artillery, under command of Col. Alfred Rhett. Its armament had been reduced to 68 guns and mortars, many of the best pieces having been removed to strengthen other fortifications about the harbor.
On the morning of July 10, 3,000 Union infantry, supported by four monitors and the artillery on Folly Island, descended on the southern end of Morris Island. Directing the attack was Brig. Gen. Truman Seymour, a company commander at Fort Sumter two years before. Within four hours, most of the Island was in his hands. The Confederate forces, outgunned and outmanned, fell back to Battery Wagner. Sumter’s guns helped to cover their retreat.
A “desperate” assault upon Wagner the next morning failed, though the parapet was briefly gained. General Gillmore established counter-batteries and tried again on the 18th. From noon until nightfall that day, “without cessation or intermission,” Federal guns poured a “storm of shot and shell upon Fort Wagner ... perhaps unequalled in history.” This was followed by an attack by some 6,000 troops, spearheaded by the 54th Massachusetts, the first U.S. black regiment to go to war. In a short, savage struggle, Seymour’s force suffered 1,500 casualties. Though one angle of the fort was gained and held for a time, the attack was repulsed.
Part of Gillmore’s map of the Charleston defenses.
Col. Alfred Rhett commanded Fort Sumter during the April 1863 ironclad attack and the first great bombardment of August-September.
Brig. Gen. Truman Seymour, who served at Fort Sumter under Anderson in 1860-61, commanded the assault troops that captured Morris Island in July 1863. He was severely wounded in the subsequent attack on Battery Wagner.