Fort Sumter, a work built upon an artificial island near the entrance of the harbor of Charleston, S. C, which it was designed to protect. It stands about 2f m. from Castle Pinckney, the fort near the point of the peninsula upon which Charleston is built, and about half that distance from Fort Moultrie on Sullivan's island. It was intended to mount 140 heavy guns, in three tiers; but at the close of 1860 the fort was still incomplete, few of the guns being mounted. The United States garrison, numbering 109 men, of whom only 63 were combatants, under Major Robert Anderson, occupied Fort Moultrie. On the night of Dec. 26 Major Anderson, learning that the secessionists had made preparations to capture Fort Moultrie and seize the other fortifications near Charleston, transferred his force to Fort Sumter. Here he was able to mount only 52 of the lighter guns. About the same time commissioners were sent by the state authorities to demand from the government of the United States the surrender of all the forts in South Carolina. President Buchanan refused, and Fort Sumter was virtually in a state of siege.

Early in January, 1861, an unsuccessful attempt was made to throw in supplies, by means of an expedition from New York in the steamer Star of the West. On April 11 Gen. Beauregard, who had been placed in command of the forces raised by the confederate government, and had constructed powerful batteries on every point commanding Fort Sumter, demanded the immediate surrender of the fort. Major Anderson refused, but said that if he was not reenforced by the 15th he would evacuate the fort; to which Beauregard responded that he would open fire at about half past 4 on the morning of April 12. Fire was accordingly opened, and in a few hours the works were seriously damaged. The bombardment was fiercely continued, but no one was hurt. The provisions and ammunition being nearly exhausted, the evacuation of the fort was agreed upon on the afternoon of the 13th, and on the 14th Major Anderson marched out with flying colors. The confederates strengthened the fort and put in a strong garrison, and until near the close of the war it formed the main defence of Charleston. In April, 1863, it was unsuccessfully bombarded by a monitor fleet under Admiral Du Pont. Still later it was subjected to a heavy fire from batteries erected on Morris island, and reduced almost to a mass of shapeless ruins; but every direct attempt to take it failed, and it fell into Union hands only when Charleston was finally abandoned by the confederates in February, 1865. (See Charleston.) On April 14, 1865, just four years after the surrender, the Union flag, the same which had been lowered in 1861, was again formally raised over the dilapidated walls of Fort Sumter.