United States Army > Army of the Potomac

September 1862 • to October >

Commanded by
Major General Joseph Hooker (wounded September 17)
Brigadier General G. Meade 
(to September 29)
Brigadier General John F. Reynolds

On September 12, 1862 the Third Corps of the Army of Virginia was redesignated the First Corps of the Army of the Potomac. The First Corps was engaged in both the Battle of South Mountain on September 14 and the Battle of Antietam on September 19, suffering heavy casualties. Joseph Hooker was wounded at Antietam. George Meade took command of the corps until John Reynolds returned from two weeks commanding the Pennsylvania Militia for Governor Curtin.

Headquarters Escort
2nd New York Cavalry, Companies A, B, I & K Captain John E. Naylor

First Division

Brigadier General Rufus King (to 9/14)
Brigadier General John P. Hatch (w 9/14)
Brigadier General Abner Doubleday
First Brigade Brigadier General J. P. Hatch (9/12 – 9/14) 
Colonel Walter Phelps, Jr. (after 9/14)
22nd New York Infantry Regiment Colonel Walter Phelps (^ 9/14)
Lt. Colonel John McKie Jr.
24th New York Infantry Regiment Captain John D. O’Brien (w 9/17)
Major Robert Oliver (after 9/29)
30th New York Infantry Regiment Colonel William M. Searing
14th New York State Militia Major William H. de Bevoise
2nd United States Sharpshooters Colonel Henry Post (w 9/17)
Second Brigade Brigadier General Abner Doubleday (^ 9/14)
Colonel W. P. Wainwright (w 9/14)
Lt. Colonel J. W. Hoffman
7th Indiana Infantry Regiment Major Ira G. Grover
76th New York Infantry Regiment Colonel William P. Wainwright (^ 9/14)
Lieutenant Chauncey Crandell (9/14)
Captain John W. Young
95th New York Infantry Regiment Major Edward Pye
56th Pennsylvania Infantry Regiment Lt. Colonel John W. Hoffman (^ 9/14)
Captain Frederick Williams
Third Brigade Brigadier General Marsena Patrick
21st New York Infantry Regiment Colonel William F. Rogers
23rd New York Infantry Regiment Colonel Henry C. Hoffman
35th New York Infantry Regiment Colonel Newton B. Lord
80th New York Infantry Regiment Lt. Colonel Theodore B. Gates
Fourth Brigade “Iron Brigade” Brigadier General John Gibbon
19th Indiana Infantry Regiment Colonel Solomon Meredith (to 9/16)
Lieutenant Colonel Alois O. Bachmann (k 9/17)
Captain William W. Dudley 
2nd Wisconsin Infantry Regiment Colonel Lucius Fairchild (w 9/14)
Major Rufus R. Dawes
6th Wisconsin Infantry Regiment Lt. Colonel Edward S. Bragg
7th Wisconsin Infantry Regiment Captain John B. Callis
Division Artillery
1st New Hampshire Battery Lieutenant Frederick M. Edgell
Battery D, 1st Rhode Island Artillery Captain John Albert Monroe
Battery L, 1st New York Artillery Captain John A. Reynolds
4th United States Artillery, Battery B Captain Joseph Campbell (w 9/17)
Lieutenant James Stewart

Second Division

Brigadier General John B. Ricketts (to 9/17)
First Brigade Brigadier General Abram Duryea
97th New York Infantry Regiment Lt. Colonel John P. Spotford
104th New York Infantry Regiment Major Lewis C. Skinner
105th New York Infantry Regiment Lt. Colonel Howard Carroll (mw 9/17)
Captain John C. Whiteside
107th Pennsylvania Infantry Regiment Colonel Thomas F. McCoy
Second Brigade Colonel William H. Christian (res. 9/19)
Colonel Peter Lyle 
26th New York Infantry Regiment Lt. Colonel Richard H. Richardson (Col. 9/19)
94th New York Infantry Regiment Lieutenant Colonel Calvin Littlefield
88th Pennsylvania Infantry Regiment Lt. Colonel George W. Gile (w 9/17)
Captain Carmack (w 9/17)
Captain Myers
90th Pennsylvania Infantry Regiment Colonel Peter Lyle (^9/17)
Lieutenant Colonel Leech
Third Brigade Brigadier General G. L. Hartsuff (w 9/17)
Colonel Richard Coulter
16th Maine Infantry Regiment Colonel Asa Wildes from Washington 9/6
12th Massachusetts Infantry Regiment Major Elisha Burbank (mw 9/17)
Captain Benjamin Cook (to 9/9)
Colonel James L. Bates
13th Massachusetts Infantry Regiment Major Jacob Parker Gould
9th New York State Militia Lt. Colonel William Atterbury
11th Pennsylvania Infantry Regiment Colonel Richard Coulter (^ 9/17)
Captain David M. Cook
Division Artillery
2nd Maine Battery Captain James A. Hall
5th Maine Battery Captain G. F. Leppien
Battery F, 1st Pennsylvania Artillery Captain Ezra P. Matthews
Pennsylvania Independent Battery C Captain James Thompson

Third Division

Brigadier General George Meade (to 9/17)
Brigadier General T. Seymour (to 9/29)
Brigadier General George Meade
First Brigade Brigadier General Truman Seymour (^ 9/12)
Colonel R. Biddle Roberts 
Brigadier General Truman Seymour
1st Pennsylvania Reserves Colonel Richard B. Roberts (except 9/12 – 9/17)
Captain William C. Talley (9/17-9/29)
2nd Pennsylvania Reserves Captain James N. Byrnes
5th Pennsylvania Reserves Colonel Joseph W. Fisher
6th Pennsylvania Reserves Colonel William Sinclair
13th Pennsylvania Reserves Colonel Hugh McNeil (mw 9/16)
Adjutant William Hartshorne
Second Brigade Colonel Albert L. Magilton
3rd Pennsylvania Reserves Lieutenant Colonel John C. Clark
4th Pennsylvania Reserves Major John Nyce
7th Pennsylvania Reserves Colonel Henry C. Bolinger (w 9/14)
Major Chauncey A. Lyman
8th Pennsylvania Reserves Major Silas M. Baily
Third Brigade Colonel Thomas F. Gallagher (w 9/14)
Lieutenant Colonel Robert Anderson
9th Pennsylvania Reserves Lieutenant Colonel Robert Anderson (^ 9/14)
Captain Samuel B. Dick
10th Pennsylvania Reserves Lieutenant Colonel Adoniram J. Warner (w 9/17)
Captain Jonathan P. Smith
11th Pennsylvania Reserves Lieutenant Colonel Samuel Jackson
12th Pennsylvania Reserves Captain Richard Gustin
Division Artillery
Battery A, 1st Pennsylvania Artillery Lieutenant John G. Simpson
Battery B, 1st Pennsylvania Artillery Captain James H. Cooper
Battery G, 1st Pennsylvania Artillery Lieutenant Frank P. Amsden
Battery C, 5th United States Artillery Captain Dunbar R. Ransom
Lieutenant Henry S. Gansevoort (9/17)