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On Thursday, August 15, 1861, Union Brigadier General Robert Anderson, the hero of Fort Sumter, was appointed to command of the newly-formed Department of the Cumberland, comprising most of the states of Kentucky and Tennessee.
Anderson would relinquish command of the department to Brigadier General William Tecumseh Sherman in October. Ill health is often cited as the reason for the change in command, but Anderson, who was reluctant to distribute arms to Kentucky Unionists, might have fallen out of favor with Lincoln.
The Department of the Cumberland would cease to exist in October, becoming a part of the Department of the Ohio, but would be resurrected in October 1862, with General William Rosecrans commanding.