U.S. Army - Army of the Potomac

First Army Corps

Major General Joseph Hooker (w 9/17)
Brigadier General G. Meade (9/17 - 9/29)
Brigadier General John F. Reynolds (after 9/29)

Recreated from the Army of Virginia, 3rd Army Corps on September 12, 1862

First Division

Brigadier General R. King (until 9/14)

Brigadier General J.P. Hatch (9/14)

Brigadier General A. Doubleday (after 9/14)

1st Brigade

Brigadier General J. P. Hatch (9/12 - 9/14)
Colonel Walter Phelps, Jr. (after 9/14)

2nd Brigade

Bde. Gen. A. Doubleday (9/12 - 9/14)

Colonel W. P. Wainwright (9/14 - 9/17)

Lt. Colonel J.W. Hoffman (after 9/17)

3rd Brigade

Brigadier General M. R. Patrick

4th Brigade

Brigadier General J. Gibbon

Second Division

Brigadier General J. B. Ricketts

1st Brigade

Brigadier General A. Duryea

2nd Brigade

Colonel W. H. Christian (9/12 - 9/18)

Colonel Peter Lyle (after 9/18)

3rd Brigade

Brigadier General G. L. Hartsuff (until 9/17)

Colonel R. Coulter (after 9/17)

Third Division

Brigadier General G. Meade (except 9/17-9/29)
Brigadier General T. Seymour (9/17-9/29)

1st Brigade

Bde. Gen. T. Seymour (except 9/12 - 9/17)
Colonel R. B. Roberts (9/17-9/29)

2nd Brigade

Colonel A. L. Majilton

3rd Brigade

Colonel T. F. Gallagher (until 9/14)

Lt. Colonel R. Anderson (9/14)

Colonel J. W. Fisher (after 9/14)

Headquarters Escort

2nd New York Cavalry Regiment, Companies A, B, I & K

Captain John E. Naylor