United States Armies and Departments
in the Eastern Theater of the Civil War
October 1862

Army of the Potomac

Major General George McClellan

The greater part of the Army of the Potomac was operating outside its department in western Maryland after the Battle of Antietam.

Dept. of Virginia

Major General John Dix

An area 60 miles around Fortress Monroe

Middle Department

Major General John E. Wool

New Jersey, Pennsylvania, Delaware, the eastern part of Maryland and the Eastern Shore of Virginia.

Washington D.C. Defenses

Maj. Gen. Nathaniel Banks (to 10/27)

Maj. Gen. Samuel Heintzelman (after 10/27)

District of Columbia, Arlington County in Virginia, and adjacent fortifications