The Battle of Perryville, Tennessee halted the Confederate invasion of Kentucky and forced Bragg’s withdrawal into Tennessee. When Don Carlos Buell failed to pursue Bragg, he was relieved of command on October 24, 1862, and replaced by General William S. Rosecrans. Buell would spend the next year and a half in Indianapolis, in military limbo, hoping that a military commission would exonerate him of blame; he claimed he had not pursued Bragg because he lacked supplies.
Exoneration never came, and he unceremoniously left military service on May 23, 1864. Although he had been offered a command at the express recommendation of Ulysses Grant, Buell declined it, alleging that it would be degrading to serve under either William Tecumseh Sherman or Edward Canby because he outranked both of them.