U.S. Army

Department of Washington

Lt. Col. Charles F. Smith (to 4/27)

Colonel Joseph K. F. Mansfield (after 4/28)

The Department of Washington was established April 9, 1861 to consist of the District of Columba, including its original territory of Alexandria County, Virginia, and the State of Maryland as far as Bladensburg.

1st Ohio Infantry Regiment

Colonel A. McCook

arrived from Ohio late April

2nd Ohio Infantry Regiment

Colonel L. Wilson

arrived from Ohio late April

1st Rhode Island Infantry Regiment

Colonel A. Burnside

arrived from Rhode Island 4/20

7th New York State Militia

Colonel M. Lefferts

arrived from New York 4/26

8th New York State Militia

Colonel George Lyons

from New York 4/20

12th New York State Militia

Colonel Daniel Butterfield

Arrived from New York via Annapolis 5/23

25th New York State Militia

Colonel M. K. Bryan

arrived from Albany 4/29

71st New York State Militia

Colonel A. S. Vosberg

arrived from Annapolis 4/26

25th Pennsylvania Infantry Regiment

Colonel Henry L. Cake

from Harrisburg 4/18

1st United States Artillery, Battery I

2nd United States Artillery, Battery E

4th United States Artillery, Battery F

From Regular Army; arrived from west 4/18

1st United States Artillery, Battery D