U.S. Army - Army of the Potomac

First Army Corps

Major General John F. Reynolds

First Division

Brigadier General James S. Wadsworth

Colonel W.M. Sealing (until 4/9)

Colonel Walter Phelps, Jr. (after 4/9)

Brigadier General Lysander Cutler

Colonel A. T. Berthoud (before 4/20)

Bde. Gen. Gabriel B. Paul (after 4/20)

Brigadier General Solomon Meredith

Second Division

Brigadier General J.C. Robinson

Colonel Adrian R. Root

Colonel Peter Lyle (until 4/21)

Brigadier General Henry Baxter (after 4/21)

Colonel Richard Coulter (until 4/10)

Colonel Samuel H. Leonard (after 4/10)

Third Division

Brigadier General Abner Doubleday

Brigadier General Thomas R. Rowley

Brigadier General Roy Stone

Unattached

1st Maine Cavalry, Co. L

Captain Constantine Taylor

Escort

Chief of Artillery

Colonel Charles Wainwright