At the time of the Civil War, Fort Pickens was a five-sided fort with corner bastions that allowed defenders to fire on anyone that approached its walls too closely. It was also a multi-level fort. One level of guns fired from within masonry rooms in the fort's walls known as casemates; another tier of guns fired over the fort's walls. Two other forts, McRee and Barrancas, completed the defenses of Pensacola Bay. All three forts were part of the Third System.
Upon secession from the Union, leaders of the Deep South states believed that they should control all the military institutions within their states. But by the time Florida seceded on January 10, 1861, U.S. Army lieutenant Adam Slemmer, commanding the forty-six man Fort Barrancas garrison, had decided that his men could not defend the fort properly. The day Florida left the Union, Slemmer moved his garrison to Fort Pickens, abandoning McRee and Barrancas. Southern troops then occupied both of those forts and the Pensacola Naval Yard. After Slemmer evacuated to Fort Pickens, the commander of southern forces in Pensacola, Colonel William Chase, demanded the surrender of Fort Pickens on January 15 and January 18, 1861. Both times Slemmer refused.
To prevent conflict before the creation of the Confederacy, Florida senator Stephen Mallory arranged a Fort Pickens truce with President James Buchanan in late January and early February 1861. This truce maintained the status quo, with both sides agreeing that they would not improve defenses. The Union garrison in Fort Pickens was denied reinforcements but allowed to land supplies. Southern troops agreed not to attack the fort. While this truce was in effect, Colonel Chase resigned his command in Pensacola and was replaced by Brigadier General Braxton Bragg, who arrived in Pensacola on March 11, 1861. Although the truce was strained in the weeks after Bragg's arrival, it held until President Abraham Lincoln reinforced Fort Pickens in April 1861.
On March 28, 1861, Lincoln decided to resupply and possibly reinforce Fort Sumter in Charleston, South Carolina, and he chose to end the Fort Pickens truce by sending reinforcements there. But Lincoln's secretary of state, William Seward, diverted the powerful U.S. Navy steam frigate Powhatan from the Sumter mission and assigned it to the Fort Pickens relief mission on his own authority. Seward's actions undermined the Union attempt to resupply Sumter, but Federal reinforcements were landed at Fort Pickens during the night of April 12, 1861. Colonel Henry Brown became the Federal garrison's new commander on April 16, 1861.
With the truce over, both sides improved their defenses until October 9, 1861, when Bragg launched the Battle of Santa Rosa Island east of Fort Pickens. This two-day engagement accomplished little. Brown's Federals repulsed the attack, inflicting eighty-seven casualties on Bragg's men while suffering only sixty-seven themselves. In response to this assault, on November 9, 1861, Federal forces in and around Fort Pickens began a two-day bombardment of Confederate defenses in Pensacola, damaging Fort McRee so severely that it did not participate in the bombardment's second day. Casualties at Fort Pickens were light, and the fort sustained little damage. But as with the Battle of Santa Rosa Island, the November bombardment had little effect on the situation at Pensacola.
Neither side seemed able to gain an advantage. There was another brief bombardment on January 1, 1862, but, as with the earlier cannonade, it had little effect. With the Union captures of Forts Henry and Donelson, and then New Orleans, however, Confederate authorities needed to shift forces to the Western Theater and decided that resources had to be moved from Pensacola. After destroying much of its facilities, the Confederates evacuated the city on May 10, 1862, and Union troops occupied Pensacola two days later.
Fort Pickens was one of few forts in the South to remain under Union control for the entire war, and Union control of Fort Pickens made the Confederate hold on Pensacola precarious and untenable, leading to the Southern evacuation in May 1862. Fort Pickens kept Southerners from using Pensacola Bay as a haven for blockade runners and, after the Confederate evacuation, Union forces restored the naval yard and used it as a repair base for vessels of the West Gulf Coast Blockading Squadron and for ships involved in the battles of Vicksburg, Port Hudson, and Mobile Bay.
Mark A. Smith
Coleman, James C., and Irene S. Coleman. Guardians on the Gulf: Pensacola Fortifications, 1698-1980. Rev. ed. Pensacola, FL: Pensacola Historical Society, 1985; Detzer, David. Allegiance: Fort Sumter, Charleston, and the Beginning of the Civil War. New York: Harcourt, 2001; Pearce, George F. Pensacola During the Civil War: A Thorn in the Side of the Confederacy. Gainesville: University Press of Florida, 2000.