Civil War Union Brigadier General. The son of noted 19th-century portrait artist Thomas Sully, he graduated from the United States Military Academy at West Point, New York, in 1841. In his pre-Civil War career, he served in the Seminole Wars, the Mexican War (where he was present at the landings at Vera Cruz), and on the American West frontier against the Cheyenne in the 1850s. First stationed at the Washington, D.C., defenses at the beginning of the Civil War, in June 1861, as a captain, he led a company of soldiers to St. Joseph, MO, to challenge a local ordinance that prevented any from flying the Union (or Confederate) flag. He was subsequently appointed Colonel and commander of the 1st Minnesota Volunteer Infantry on March 1, 1862. He commanded the unit in the Peninsular Campaign, and commanded a brigade during subsequent Seven Days Battles. After again commanding his regiment at the September 17, 1862 Battle of Antietam, he was commissioned Brigadier General, US Volunteers on September 26, 1862. He commanded a II Corps brigade in the Army of the Potomac at the December 1862 Battle of Fredericksburg and just prior to the May 1863 Battle of Chancellorsville. A few days before Chancellorsville, he was removed from his brigade by division commander Major General John Gibbon for General Sully's inability to discipline mutinying soldiers from the 34th New York Infantry. General Sully was sent to the District of Dakota to serve under General John Pope, and fought successful campaigns against hostile Sioux Indians in Minnesota. Brevetted Brigadier General and Major General, US Regular Army upon the conclusion of the Civil War, he would go on to serve as Lieutenant Colonel of the 3rd United States Infantry, and as Colonel and commander of the 21st United States Infantry after the war. He died in 1879 while in command of the United States Army post at Fort Vancouver in the Washington Territory. He was also a noted artist himself, often painting frontier scenes during his posting.