U.S. Army - Army of the Potomac - Twelfth Army Corps

First Division

Brigadier General George Gordon (until 10/20)

Brigadier General Alpheus Williams

First Brigade

Colonel J. F. Knipe

5th Connecticut Infantry Regiment

10th Maine Infantry Regiment

28th New York Infantry Regiment

Captain William H. H. Mapes (to 10/6)

Colonel Edwin F Brown

46th Pennsylvania Infantry Regiment

Lieutenant Colonel Selfridge

124th Pennsylvania Infantry Regiment

Colonel Joseph W. Hawley

to 2nd Bde. (see below)

125th Pennsylvania Infantry Regiment

Colonel Jacob Higgins

to 2nd Bde. (see below)

128th Pennsylvania Infantry Regiment

Colonel Joseph A. Matthews

Second Brigade

Colonel George L. Andrews (10/3 - 10/6)

Bde. Gen. T. L. Kane

organized 10/20

20th Connecticut Infantry Regiment

123rd New York Infantry Regiment

Colonel Archibad L. McDougall

from New York 9/5

127th New York Infantry Regiment

Colonel William Gurney

From Def. Washington, Abercrombie's Div.

to 4th Bde. (see below)

137th New York Infantry Regiment

Colonel David Ireland

from New York 9/27; to 4th Bde. (see below)

138th New York Infantry Regiment

Colonel Joseph Welling

from New York 9/12; to 4th Bde. (see below)

140th New York Infantry Regiment

Colonel Patrick O'Rorke

from Defences of Washington
to 2nd Div., 2nd Bde.

145th New York Infantry Regiment

Colonel Edward L. Price

from New York 9/30

to 2nd Div., 2nd Bde.

149th New York Infantry Regiment

Colonel Henry A. Barnum

from Defences Washington, Casey's Div. 9/26

to 4th Bde. (see below)

124th Pennsylvania Infantry Regiment

Colonel Joseph W. Hawley

from 1st Bde. (see above)

125th Pennsylvania Infantry Regiment

Colonel Jacob Higgins

from 1st Bde. (see above)

Third Brigade

Colonel Thomas H. Ruger (until 10/20)

Bde. Gen. George Gordon (10/20 - 10/26)

27th Indiana Infantry Regiment

Colonel Silas Colgrove

2nd Massachusetts Infantry Regiment

Colonel George L. Andrews

13th New Jersey Infantry Regiment

Colonel Ezra A. Carman

107th New York Infantry Regiment

29th Pennsylvania Infantry Regiment

Colonel John K. Murphy

3rd Wisconsin Infantry Regiment

Fourth Brigade

Colonel George L. Andrews (10/6 - 10/26)

organized 10/6

127th New York Infantry Regiment

Colonel William Gurney

from 2nd Bde. (see above)

to Def. Washington, Abercrobie's Div., 3rd Bde.

137th New York Infantry Regiment

Colonel David Ireland

from 2nd Bde. (see above)

to 2nd Div.

138th New York Infantry Regiment

Colonel Joseph Welling

from 2nd Bde. (see above)

to Def. Washington, Haskin's Div., 2nd Bde.

149th New York Infantry Regiment

Colonel Henry A. Barnum

from 2nd Bde. (see above)

to 2nd Div., 3rd Bde.

Artillery

1st New York Artillery, Battery K

1st New York Artillery, Battery M

10th New York Independent Battery