 Although he was successful at reviving the "esprit de corps" of his army by better distributing supplies and food, he was unable to effectively lead the army in the field, and his inaction during the Battle of Chancellorsville led to his resignation of his command.Transferred to the Department of the Cumberland, he commanded the XI and XII Corps during several western campaigns and distinguished himself during the Battle of Lookout Mountain.Hooker resigned his command upon the promotion of Maj. Gen. Oliver O. Howard to the command of the Army of the Tennessee, a post to which Hooker felt entitled.