 He led his regiment during the Peninsula Campaign, sustaining a minor wound at Glendale.Sully was promoted to brigadier general on September 26 and led a brigade in the II Corps during the Battle of Fredericksburg, but on May 1, 1863, was removed from command by his division commander, Brig.Gen John Gibbon after failing to suppress a mutiny by the 34th New York when several of its companies refused to fight on the grounds that their two-year enlistment term was about to expire.