United States Army > Army of the Potomac


< to February • March 1864 • to April >

Commanded by:
Major General George Sykes (to 3/23)
Major General Gouverneur K. Warren

On March 23-25 the First Corps was dissolved and merged into the Fifth Corps. The existing Second Division of the Fifth Corps (the badly depleted U.S. Regulars) was consolidated into a single brigade which became the Fourth Brigade of the First Division. A new Fourth Division was created from three First Corps Brigades.

Provost Guard

12th New York Infantry, Cos. D&F Major Henry W. Ryder

First Division

Brigadier General J. J. Bartlett
First Brigade Colonel W. S. Tilton (to 3/25)
18th Massachusetts Infantry Regiment to 3 Brig. (below)
22nd Massachusetts Infantry Regiment to 2 Brig. (below)
1st Michigan Infantry Regiment Lieutenant Colonel William A. Throop to 3 Brig. (below)
118th Pennsylvania Infantry Regiment Lieutenant Colonel James Gwynn to 3 Brig. (below)
Second Brigade Colonel J. B. Sweitzer
Colonel J. Hayes
9th Massachusetts Infantry Regiment Colonel Patrick R. Guiney (after 2/3)
22nd Massachusetts Infantry Regiment from 1 Brig. (above)
32nd Massachusetts Infantry Regiment Lieutenant Colonel Luther Stephenson
4th Michigan Infantry Regiment Lieutenant Colonel George Lumbard
62nd Pennsylvania Infantry Regiment Lieutenant Colonel James C. Hull
Third Brigade Colonel J. Hayes
20th Maine Infantry Regiment
18th Massachusetts Infantry Regiment from 1 Brig. (above)
1st Michigan Infantry Regiment Lieutenant Colonel William A. Throop from 1 Brig. (above)
16th Michigan Infantry Regiment Lieutenant Colonel Norval E. Welch
44th New York Infantry Regiment Lieutenant Colonel Freeman Conner
83rd Pennsylvania Infantry Regiment Major William H. Lamont
118th Pennsylvania Infantry Regiment Lieutenant Colonel James Gwynn from 1 Brig. (above)
Fourth Brigade Brigadier General Romeyn Ayers organized 3/25

140th New York Infantry Regiment

Lieutenant Colonel Louis Ernst

146th New York Infantry Regiment

Colonel David T. Jenkins from 2 Div. 3 Brig. (below)

91st Pennsylvania Infantry Regiment

Lieutenant Colonel Joseph H. Sinex from 2 Div. 3 Brig. (below)

155th Pennsylvania Infantry Regiment

Lieutenant Colonel John H. Cain from 2 Div. 3 Brig. (below)
2nd United States Infantry Regiment Captain Samuel A. McKee from 2 Div. 1 Brig. (below)

11th United States Infantry Regiment

Major DeLancey Floyd-Jones from 2 Div. 1 Brig. (below)

12th United States Infantry Regiment

Captain Thomas S. Dunn from 2 Div. 1 Brig. (below)

14th United States Infantry Regiment

Major Grotius R. Giddings from 2 Div. 1 Brig. (below)

17th United States Infantry Regiment

Lieutenant Colonel James D. Greene from 2 Div. 1 Brig. (below)

Second Division

Before Reorganization on March 23

Brigadier General Romeyn B. Ayres
to 1 Div. 4 Brig. (above)
First Brigade (until 3/23) Major L. B. Brown
2nd United States Infantry Regiment
Companies B, C, F, I & K
Captain Samuel A. McKee to 1 Div. 4 Brig.
11th United States Infantry Regiment
1st Bn. Companies B, C, D, E, F & G
2nd Bn. Companies C & D
Major DeLancey Floyd-Jones to 1 Div. 4 Brig.
12th United States Infantry
1st Bn. Companies A, B, C, D & G
2nd Bn. Companies A, C & D
Captain Thomas S. Dunn to 1 Div. 4 Brig.
14th United States Infantry
1st Bn. Companies A, B, D, E, F & G
2nd Bn. Companies F & G
Major Grotius R. Giddings to 1 Div. 4 Brig.
17th United States Infantry Regiment
1st Bn. Companies A, C, D, G & H
2nd Bn. Companies A & B
Leutenant Colonel James D. Greene to 1 Div. 4 Brig.
Third Brigade (until 3/23) Colonel George Ryan
140th New York Infantry Regiment Lieutenant Colonel Louis Ernst to 1 Div. 4 Brig.
146th New York Infantry Regiment Colonel David T. Jenkins to 1 Div. 4 Brig.
91st Pennsylvania Infantry Regiment Lieutenant Colonel Joseph H. Sinex to 1 Div. 4 Brig.
155th Pennsylvania Infantry Regiment Lieutenant Colonel John H. Cain to 1 Div. 4 Brig.

Second Division

After Reorganization on March 23

Brigadier General Henry Baxter
First Brigade (after 3/23) Colonel Samuel H. Leonard
16th Maine Infantry Regiment Lieutenant Colonel Charles W. Tilden from 1 Corps,
2 Div. 1 Brig.
13th Massachusetts Infantry Regiment
39th Massachusetts Infantry Regiment Colonel Phineas S. Davis
104th New York Infantry Regiment Colonel Gilbert G. Prey
107th Pennsylvania Infantry Regiment Major Henry J. Shaefer
3rd United States Infantry Regiment Captain Andrew Sheridan
Second Brigade (after 3/23) Brigadier General H. Baxter
12th Massachusetts Infantry Regiment Major Benjamin F. Cook from 1 Corps,
2 Div. 2 Brig.
83rd New York Infantry (9th NYSM) Colonel Joseph A. Moesch
97th New York Infantry Regiment Major Charles Northrup
11th Pennsylvania Infantry Regiment Colonel R. Coulter
88th Pennsylvania Infantry Regiment Captain Edmund Y. Patterson
90th Pennsylvania Infantry Regiment Lieutenant Colonel William A. Leech
Third Brigade  (after 3/23) Colonel Nathan T. DuShane
1st Maryland Infantry Regiment  Lieutanant Colonel John W. Wilson from 1 Corps,
3 Div. 2 Brig.
4th Maryland Infantry Regiment  Colonel Richard N. Bowerman
7th Maryland Infantry Regiment   Colonel Charles E. Phelps
8th Maryland Infantry Regiment  Colonel Andrew W. Denison

Third Division

Colonel William McCandless
First Brigade Colonel William O. Talley
1st Pensylvania Reserves Regiment
2nd Pensylvania Reserves Regiment Lieutenant Colonel George A. Woodward
6th Pensylvania Reserves Regiment Lieutenant Colonel Wellington H. Ent
11th Pensylvania Reserves Regiment Colonel Samuel M. Jackson
1st Pennsylvania Rifles (13th Reserves) Major William R. Hartshorne
Third Brigade Colonel Joseph W. Fisher
5th Pensylvania Reserves Regiment Lieutenant Colonel George Dare
9th Pensylvania Reserves Regiment Lieutenant Colonel James M. Snodgrass
10th Pensylvania Reserves Regiment Colonel Adironiram J. Warner
12th Pensylvania Reserves Regiment

Fourth Division

Brigadier General James Wadsworth created 3/25
First Brigade (“Iron Brigade”) Brigadier General Lysander Cutler
19th Indiana Infantry Regiment Colonel Samuel J. Williams from
1 Corps
1 Div. 1 Brig.
24th Michigan Infantry Regiment Colonel Henry A. Morrow
1st New York Sharpshooter Battalion Captain Joseph C. Arnold
2nd Wisconsin Infantry Regiment Colonel William W. Robinson
6th Wisconsin Infantry Regiment Colonel Edward Bragg
7th Wisconsin Infantry Regiment Major Mark Finnicum
Second Brigade Brigadier General J. C. Rice
7th Indiana Infantry Regiment Colonel Ira G. Grover from
1 Corps
1 Div. 2 Brig.
14th New York State Militia (84th N.Y.) Colonel Edward B. Fowler
76th New York Infantry Regiment Major John W. Young
95th New York Infantry Regiment Major Edward Pye
147th New York Infantry Regiment Major George Harney
56th Pennsylvania Infantry Regiment Colonel J. W. Hoffman
Third Brigade Colonel Roy Stone
121st Pensylvania Infantry Regiment Major Alexander Biddle from
1 Corps
3 Div. 2 Brig.
142nd Pensylvania Infantry Regiment Lieutenant Colonel Alfred B. McCalmont
143rd Pensylvania Infantry Regiment
149th Pensylvania Infantry Regiment Lieutenant Colonel Walton Dwight
150th Pensylvania Infantry Regiment Captain Horatio Bell

Artillery

Captain Augustus P. Martin
3rd Massachusetts Battery Lieutenant Aaron F. Walcott
5th Massachusetts Battery Captain Charles A Phillips
1st New York Artillery, Battery C Captain Almont Barnes to Artilery Reserve, 3rd Brig.
1st New York Artillery, Battery D from 1st Corps Artilery
1st New York Artillery, Battery E from 1st Corps Artilery
1st New York Artillery, Battery H from 1st Corps Artilery
1st New York Artillery, Battery L from 1st Corps Artilery
4th New York Heavy Artillery, 2nd Battalion from 22 Corps, DeRussey’s Div., 3rd Brig.
1st Ohio Artillery, Battery L Captain Frank C. Gibbs
1st Pennsylvania Artillery, Battery B from 1st Corps Artilery
3rd United Artillery, Batteries F & K Lieutenant John C. Turnbull to Army Artillery Reserve
4th United Artillery, Battery B from 1st Corps Artilery
5th United Artillery, Battery D