- May 27, 1861
- July 25, 1862
- On May 27, 1861, the War Department issued General Orders No. 20, creating a new Military Geographical Department which was subsequently referred to as the Department of Northeastern Virginia.
- The Department of Northeastern Virginia encompassed “All that part of Virginia, east of the Alleghany mountains and north of James river, except Fort Monroe and sixty miles around the same . . . .”
- Brigadier General Irvin McDowell was the first and only commander of the Department and Army of Northeastern Virginia.
- The Army of Northeastern Virginia consisted of about 30,000 to 35,000 raw recruits.
- Many soldiers of the Army of Northeastern Virginia were three-month volunteers.
- The Army of Northeastern Virginia consisted of five divisions led by Brigadier General Daniel Tyler, Colonel David Hunter, Colonel Samuel Heintzelman, Brigadier General Theodore Runyon, and Colonel D. S. Miles.
- There is scant historical evidence that The Army of Northeastern Virginia was ever officially ascribed that name.
- On July 21 the Confederate Army of the Potomac, reinforced by the Army of the Shenandoah, routed the Army of Northeastern Virginia at the First Battle of Bull Run.
- On July 25, 1862, the War Department merged the Department of Northeastern Virginia with the Department of Washington to create the Division of the Potomac.