 On October 16, 1863, the Department of the Ohio (along with the Department of the Tennessee and the Department of the Cumberland) became part of the Military Division of the Mississippi, under the overall command of Maj. Gen. Ulysses S. Grant.Due to illness, Burnside asked to be relieved of command after the Battle of Fort Sanders and was replaced by Maj. Gen. John G. Foster on December 9.On February 9, 1864, Maj. Gen. John M. Schofield assumed command of the Department of the Ohio.