Fort Barrancas mostly by enslaved African-American workers. January 8, 1861, more than three months before the American Civil War officially started at Fort Sumter, South Carolina, a company of 50 U.S. Army soldiers stationed at Fort Barrancas, under the command of John H. Winder fired upon a militia. This militia was Florida state troops under Colonel William Henry Chase demanding that the U.S. troops surrender the fort. Lieutenant Adam J. Slemmer, acting commander in Winder's absence, had the troops fire shots meant to repel the militia. Lt Slemmer knew that Fort Pickens was easier to defend, so he spiked the guns at
Battle of Fort Sumter positions except Fort Sumter were to be seized. State troops quickly occupied Fort Moultrie (capturing 56 guns), Fort Johnson on James Island, and the battery on Morris Island. On December 27, an assault force of 150 men seized the Union-occupied Castle Pinckney fortification, in the harbor close to downtown Charleston, capturing 24 guns and mortars without bloodshed. On December 30, the Federal arsenal in Charleston was captured, resulting in the acquisition of more than 22,000 weapons by the militia. The Confederates promptly made repairs at Fort Moultrie and dozens of new batteries and defense positions were constructed throughout the Charleston