Sedgwick's Civil War assignments included: major, 1st Cavalry (since March 3, 1855); lieutenant colonel, 2nd Cavalry (March 16, 1861); colonel, 1st Cavalry (April 25, 1861); colonel, 4th Cavalry (change of designation August 3, 1861); brigadier general, USV (August 31, 1861); commanding 2nd Brigade, Heintzelman's Division, Army of the Potomac (October 31 1861-February 9, 1862); commanding Stone's (old) Division, Army of the Potomac (February 9-March 13, 1862); commanding 2nd Division, 2nd Corps, Army of the Potomac (March 13-September 17, 1862); major general, USV July 4, 1862); commanding 2nd Corps, Army of the Potomac (December 26, 1862-January 26, 1863); commanding 9th Corps, Army of the Potomac January 16 - February 5, 1863); and commanding 6th Corps, Army of the Potomac (February 4 1863-April 6, 1864 and April 13-May 9, 1865).
http://www.civilwarhome.com/sedgwickbio.htm