United States Armies in the East > Department of Pennsylvania
< to May • June 1861 • to July >
Commanded by Major General Robert Patterson
| Unattached | ||
| 2nd Pennsylvania Infantry Regiment | Colonel Frederick S. Stumbaugh | to 2 Brig. 2 Div. (below) |
| 3rd Pennsylvania Infantry Regiment | Colonel Francis P. Minier | to 2 Brig. 2 Div. (below) 6/1 |
| 7th Pennsylvania Infantry Regiment | Colonel William I. Irwin | to 3 Brig. 1 Div. (below) 6/14 |
| 8th Pennsylvania Infantry Regiment | Colonel A.H. Emley | to 3 Brig. 1 Div. (below) 6/14 |
| 10th Pennsylvania Infantry Regiment | Colonel Sullivan A. Meredith | to 3 Brig. 1 Div. (below) 6/16 |
| 13th Pennsylvania Infantry Regiment | Colonel Thomas A. Rowley | to 4 Brig. 1 Div. (below) 6/4 |
| 14th Pennsylvania Infantry Regiment | Colonel John W. Johnston | to 5 Brig. 2 Div. (below) 6/3 |
| 17th Pennsylvania Infantry Regiment | Colonel Francis E. Patterson | at Rockville and Edward’s Ferry |
| 20th Pennsylvania Infantry Regiment | Colonel Wiliam H. Gray | to 3rd Brig. 1 Div. 6/1 |
| 1st Division | Brig. Gen. George Cadwallader | created 6/1 |
| 1st Brigade | Col. George H. Thomas | |
| 3rd Brigade | Brig. Gen. A. S. Williams | |
| 4th Brigade | Col. J. C. Longenecker | |
| 2nd Division | Maj. Gen. William H. Keim | created 6/1 |
| 2nd Brigade | Brig. Gen. G. C. Wynkoop | |
| 5th Brigade | Brig. Gen. J. S. Negley | |
| 6th Brigade | Col. John J. Abercrombie | |
| Unattached | ||
| 1st United States Artillery, Battery E | from Fort Hamilton, New York 6/3 | |
| 1st United States Artillery, Battery H | from Fort Hamilton, New York 6/3 | |