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
Fort Sumter first-day cover was issued that day. On June 28, 2015, in the aftermath of the events of June 17, 2015, when a mass shooting took place at Emanuel African Methodist Episcopal Church in downtown Charleston, South Carolina, the five small flags that were arranged in a semi-circle around the large flagpole flying the 50-star United States flag at Fort Sumter were lowered so that the South Carolina flag could be flown at half mast. Those flown include (1) a 33-star United States flag, (2) a Confederate First National Flag (), (3) a South Carolina State Flag, (4) a Confederate Second