The plan for the Battle of Chancellorsville was strategically daring. Hooker assigned Stoneman a key role in which his Cavalry Corps would raid deeply into Robert E. Lee's rear areas and destroy vital railroad lines and supplies, distracting Lee from Hooker's main assaults. However, Stoneman was a disappointment in this strategic role. The Cavalry Corps got off to a good start in May 1863, but quickly bogged down after crossing the Rapidan River. During the entire battle, Stoneman accomplished little, and Hooker considered him one of the principal reasons for the Union defeat at Chancellorsville. Hooker needed to deflect criticism from himself and relieved Stoneman of his cavalry command, sending him back to Washington, D.C., for medical treatment (chronic hemorrhoids, exacerbated by cavalry service), where in July he became a Chief of the U.S. Cavalry Bureau, a desk job. A large cavalry supply and training depot on the Potomac River was named Camp Stoneman in his honor.