|Brig. Gen. John M. Brannan, U.S.V.|
The following is from General Orders No. 3. issued from the Headquarters of the Army in Washington, D.C., on January 11, 1862:
I. A new military department, to be known as the Department of Key West, is hereby constituted, with the following bounds: Key West, the Tortugas, and the main-land on the west coast as far as Apalachicola and to Cape Canaveral on the east coast.
Brig. Gen. J.M. Brannan, U.S. volunteers, is assigned to the command. - I. Thomas, Adjutant-General, January 11, 1862.
The orders were issued by command of Major General George B. McClellan, who then served as general-in-chief of the Union army.
An 1841 graduate of the U.S. Military Academy at West Point, General Brannan had served during the Mexican War (now generally called the Mexican-American War) where he fought in the Battles of Vera Cruz, Cerro Gordo, Churubusco and Mexico City, among others. He was badly wounded at Mexico City, but recovered and went on to serve in Florida during the years between the end of that war and the beginning of the War Between the States.
Brannan's name would figure prominently in Florida over the next several years.