U.S. Army - Army of the Potomac

First Army Corps

Major General John F. Reynolds

As the First Corps launched into the pursuit of Lee on his invasion of Pennsylvania two brigades dissolved in the 1st Division as regiments mustered out at the end of their terms. Stannard's brigade of Vermont regiments from the Washington defences was attached to the 3rd Division, although it would not physically join the Corps until Gettysburg.

First Division

Brigadier General J.S. Wadsworth

1st Brigade

Colonel E. B. Fowler (until 6/13)

Brigadier Gen. S. Meredith (after 6/13)

dissolved as regiments mustered out.
4th Brigade redesignated as 1st Brigade 6/16

2nd Brigade

Brigadier General L. Cutler

3rd Brigade

Brigadier General G. B. Paul

dissolved 6/16

4th Brigade

Brigadier General S. Meredith

became 1st Brigade 6/16

Second Division

Brigadier General J.C. Robinson

1st Brigade

Colonel S. H. Leonard (until 6/17)

Brigadier General G. Paul (after 6/17)

2nd Brigade

Brigadier General H. Baxter

Third Division

Brigadier General A. Doubleday (until 6/30)

Brigadier General T. A. Rowley (after 6/30)

1st Brigade

Brigadier Gen. J. R. Rowley (until 6/30)

Colonel C. Biddle (after 6/30)

2nd Brigade

Brigadier General Roy Stone

3rd Brigade

Bde. Gen. George Stannard

from 22nd Corps, Abercrombie's Div, 2nd Bde.

Artilery Brigade

Colonel Charles S. Wainwright

2nd Maine Battery

Captain James A. Hall

5th Maine Battery

Captain Greenleaf T. Stevens

Battery E, 1st New York Artillery

attached to battery L (see below)

from 6th Corps, 2nd Div. Artillery

Battery L, 1st New York Artillery

Captain Gilbrert H. Reynolds

Battery B, 1st Pennsylvania Artillery

Captain James H. Cooper

Battery B, 4th United States Artillery

Lieutenant James Stewart