There were five corps in the Union Army designated as II Corps (Second Army Corps) during the American Civil War. These formations were the Army of the Cumberland II Corps commanded by Thomas L. Crittenden from October 24, 1862 to November 5, 1862, later renumbered XX Corps; the Army of the Mississippi II corps led by William T. Sherman from January 4, 1863 to January 12, 1863, renumbered XV Corps; Army of the Ohio II Corps commanded by Thomas L. Crittenden from September 29, 1862 to October 24, 1862, transferred to Army of the Cumberland; Army of Virginia II Corps led by Nathaniel P. Banks from June 26, 1862 to September 4, 1862 and Alpheus S. Williams from September 4, 1862 to September 12, 1862, renumbered XII Corps; and the Army of the Potomac II Corps from March 13, 1862 to June 28, 1