Union Army department, 1861 to 1862
Department of Florida, was the military administrative department established by the Union Army. The Department of Florida was established on April 13, 1861 to defend and administer the few remaining Federal installations remaining in Florida. Following the secession of Florida in January 1861, Florida troops seized most Federal property in the state with the exceptions of Fort Zachary Taylor at Key West and Fort Pickens at Pensacola. The Union Navy would use the port of Key West to establish a blockade of the Atlantic and Eastern Gulf coasts of the Confederacy, with the South Atlantic Blockading Squadron and the East Gulf Blockading Squadron.
On January 11, 1862, Key West and the coastline from Cape Canaveral to the Apalachicola River were detached from the Dept of Florida to form the Department of Key West under command of Brig. Gen. John M. Brannan, U. S. Army.
On March 15, 1862, the Department of Florida was merged into the Department of the South.
Department of Florida (1865-66).
At the end of the Civil War, a new Department of Florida, subordinate to the Military Division of the Gulf, (1865–66) was established by the United States Army on June 27, 1865. It remained until 1866 when it was merged into the Department of the Gulf, (1866–67).
Notes.
 ;templatestyles src="Reflist/styles.css" / ;