answers.input_text: short
answers.span_text: George B. McClellan
questions: who was the successful commanding general of the northern forces in the civil war
name: George B. McClellan
contexts: George B. McClellan 1861 photograph by Mathew Brady 24th Governor of New Jersey In office January 15 , 1878 -- January 18 , 1881 Preceded by Joseph D. Bedle Succeeded by George C. Ludlow 4th Commanding General of the United States Army In office November 1 , 1861 -- March 11 , 1862 Preceded by Winfield Scott Succeeded by Henry Halleck Personal details George Brinton McClellan ( 1826 - 12 - 03 ) December 3 , 1826 Philadelphia , Pennsylvania October 29 , 1885 ( 1885 - 10 - 29 ) ( aged 58 ) Orange , New Jersey Political party Democratic Spouse ( s ) Mary Ellen Marcy ( `` Nelly '' ) McClellan Parents George McClellan Mary ( Brinton ) McClellan Alma mater United States Military Academy , West Point , New York Profession Soldier ( General ) Politician Signature Military service Nickname ( s ) Little Mac The Young Napoleon Allegiance United States Union Service / branch United States Army Union Army Years of service 1846 -- 1857 1861 -- 1864 Rank Major General Commands Department of the Ohio Army of the Potomac Battles / wars Mexican -- American War ( 1846 - 1848 ) American Civil War ( 1861 - 1865 ) Battle of Rich Mountain Peninsula Campaign Seven Days Battles Maryland Campaign Battle of South Mountain Battle of Antietam