| II Corps | |
|---|---|
&sq=&lang=&file=File:IIcorpsbadge.png) Army of the Potomac II Corps badge (trefoil) | |
| Active | 1862–1865 |
| Country |  United States |
| Branch | &sq=&lang=&file=File:Seal_of_the_United_States_Department_of_War.png){kind=small} Union Army |
| Type | Army Corps |
| Size | Corps |
| Part of | Army of the Potomac |
| Motto(s) | "Clubs are trumps" |
| Engagements | American Civil War |
| Commanders | |
| Notable commanders | Edwin Vose Sumner Darius N. Couch Winfield Scott Hancock Gouverneur K. Warren Andrew A. Humphreys |
| Insignia | |
| 1st Division | &sq=&lang=&file=File:IIcorpsbadge1.png){kind=small} |
| 2nd Division | &sq=&lang=&file=File:IIcorpsbadge2.png){kind=small} |
| 3rd Division | &sq=&lang=&file=File:IIcorpsbadge3.png){kind=small} |
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 XXI 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, 1865.
Of these five, the one most widely known was the Army of the Potomac formation, the subject of this article.