In May 1861, William T. Sherman was appointed colonel in the 13th U.S. Infantry, and was assigned command of a brigade under General William McDowell in Washington, D.C. He fought in the First Battle of Bull Run, in which Union troops were badly beaten. He was then sent to Kentucky and became deeply pessimistic about the war, complaining to his superiors about shortages while exaggerating the enemy's troop strength. He was eventually put on leave, considered unfit for duty. The press picked up on his troubles and described him as "insane." It is believed Sherman suffered from a nervous breakdown.

In mid-December 1861, Sherman returned to service in Missouri and was assigned rear-echelon commands. In Kentucky, he provided logistical support for Brigadier General Ulysses S. Grant's capture of Fort Donelson in February 1862. The following month, Sherman was assigned to serve with Grant in the Army of West Tennessee. His first test as a commander in combat came at Shiloh.

Service Civil War