Thomas, promoted to major general effective April 25, 1862, was given command of the Right Wing, consisting of four divisions from Grant's former Army of the Tennessee and one from the Army of the Ohio.
Thomas blev forfremmet til generalmajor ved virkning fra 25. april 1862 fik kommandoen over højre fløj, som bestod af 4 divisioner fra Grant's Army of the Tennessee og en fra Army of the Ohio.