During the Civil War, Confederate military authorities used different levels of operational command to oversee their growing military forces and to respond to federal campaigns against the south. The military department proved to be one of the more effective levels of command for territorial areas. The department commanders reported directly to the Confederate War Department and Confederate president Jefferson Davis. Initially Confederate officials created military departments only for areas directly under federal attack. As the war developed, they created departments to cover the entire Confederacy. Confederate authorities restructured the departments as the war developed, and Union forces captured some parts of the Confederacy or military campaigns created new military needs in geographical areas. Some old departments were dissolved, or divided, and territories placed within new departments designed for contemporary needs.
The first department to include parts of Mississippi was the Department of Mississippi and East Louisiana, established on October 1, 1862. It existed until January 28, 1864, when Confederate authorities created the new department of Alabama and East Mississippi. That department lasted until August 15, 1864, and the creation of the Department of Alabama, Mississippi, and Eastern Louisiana, which lasted until May 1865 and the end of the war. (Americancivilwarhighcommand.com)
