Assigned next to the Gettysburg Campaign, the 72nd New York fought in the Battle of Gettysburg under the command of Colonel John Austin. Positioned near the Emmettsburg Road, the regiment was forced to retreat when the Third Corps was routed from its advance position. By the time the second day's fight was over, Austin and one-third of the regiment had become casualties, as had Sickles, the regiment's founder, whose leg was so badly damaged by a stray cannon ball that it required amputation. When the engagement was over, the regiment was ordered to pursue Confederate troops from Gettysburg into Maryland and Virginia, and re-engaged with the enemy in the battles of Wapping Heights (July 23), Bristoe Station (October 14) and Kelly's Ford (November 7), as well as in the Mine Run Campaign (November 27–December 2).