s ▁and ▁Burn side ' s ▁sl ugg ish ness , ▁saved ▁Lee ' s ▁Army ▁of ▁Northern ▁Virginia ▁and ▁allowed ▁them ▁to ▁bare ly ▁hold ▁off ▁the ▁Union ▁in ▁Maryland . ▁ ▁Corps ▁organization ▁under ▁Lee ▁Although ▁the ▁Army ▁of ▁Northern ▁Virginia ▁sw elled ▁and ▁sh rank ▁over ▁time , ▁its ▁units ▁of ▁organization ▁consisted ▁primarily ▁of ▁corps , ▁earlier ▁referred ▁to ▁as ▁" w ings " ▁or ▁" commands ": ▁ ▁First ▁Corps ▁( Long street ' s ▁Corps ) ▁ ▁Second ▁Corps ▁( Jack son ' s ▁Corps ▁in ▁ 1 8 6 2 / 1 8 6 3 ) ▁ ▁Third ▁Corps ▁( A . P . ▁Hill ' s ▁Corps ) ▁ ▁Four th ▁Corps ▁( And erson ' s ▁Corps ) ▁ ▁Caval ry ▁Corps ▁ ▁Camp aign s ▁and ▁batt les ▁The ▁Army ▁fought ▁in ▁a ▁number ▁of ▁campaign s ▁and ▁batt les , ▁including : ▁ ▁On ▁April ▁ 9 , ▁ 1 8 6 5 , ▁the ▁Army ▁of ▁Northern ▁Virginia ▁surrender ed ▁to ▁the ▁Army ▁of ▁the ▁Pot om ac ▁at ▁App om atto x ▁Court ▁House , ▁effectively ▁ending ▁the ▁Civil ▁War , ▁with ▁General ▁Lee ▁signing ▁the ▁papers ▁of ▁surrender ▁to ▁General ▁U ly ss es ▁S . ▁Grant . ▁ ▁The ▁day ▁after ▁his ▁surrender , ▁Lee ▁issued ▁his ▁F are well ▁Address ▁to ▁the ▁Army ▁of ▁Northern ▁Virginia . ▁ ▁Organ ization ▁of ▁the ▁Army ▁ ▁Department ▁of ▁Northern ▁Virginia , ▁October ▁ 2 2 , ▁ 1 8