< to July • August 1861

Commanded by Brigadier General Daniel Tyler* 

The 1st Division was discontinued on August 17, 1861

First Brigade Colonel Erasmus Keyes
2nd Maine Infantry Regiment Colonel Charles D. Jameson  to Potomac, Fort Corcoran
2nd Connecticut Infantry Regiment Colonel A. H. Terry  mustered out 8/7
3rd Connecticut Infantry Regiment Colonel J. Chatfield  mustered out 8/12
Second Brigade Brig. Gen. Robert C. Schenck**
2nd New York State Militia Colonel G. W. B. Tompkins to Potomac, Stone’s Brig.
New York Artillery, Battery B Captain Thaddeus P. Mott to Potomac, Smith’s Brig.
2nd United States Artillery, Battery E Captain Carlisle to Dept. Potomac
Third Brigade Colonel W. T. Sherman
13th New York Infantry Regiment Colonel Isaac F. Quinby  to Potomac, Fort Corcoran
79th New York Infantry Regiment Lt. Colonel S.M. Elliott  to Potomac, Smith’s Brig.
2nd Wisconsin Infantry Regiment Colonel P. S. Coon  to Potomac, Fort Corcoran
3rd United States Artillery, Battery E Captain Ayers  to Dept. Potomac, Sherman’s Brig.
Fourth Brigade Colonel Israel Richardson
1st Massachusetts Infantry Regiment Colonel R. Cowdin  to Dept. Potomac, Hooker’s Brig.
12th New York Infantry Regiment Colonel E. L. Walrath  to Dept. Potomac, Richardson’s Brig.
2nd Michigan Infantry Regiment Major A. W. Williams  to Dept. Potomac, Richardson’s Brig.
3rd Michigan Infantry Regiment Colonel D. McConnel  to Dept. Potomac, Richardson’s Brig.
1st United States Artillery, Battery G Lieutenant J. Edwards  to Dept. Potomac, Richardson’s Brig.
2nd United States Artillery, Battery M Captain H. J. Hunt  to Dept. Potomac, Franklin’s Brig.

*Tyler’s commission was in the Connecticut militia
**Schenk’s commission was in the United States Volunteers