Issued by the U.S. War Department on July 25, 1861, General Orders No. 47 combined the departments of Washington and Northeastern Virginia into a division, with Major General George B. McClellan commanding.
GENERAL ORDERS NO. 47
War Dep’t, Adjutant General’s Office
Washington, July 25, 1861
There will be added to the Department of the Shenandoah, the counties of Washington and Allegheny in Maryland, and such other parts of Virginia as may be covered by the Army in its operations; and there shall be added to the Department of Washington, the counties of Prince George, Montgomery and Frederick.
The remainder of Maryland and all of Pennsylvania and Delaware will constitute the Department of Pennsylvania, Headquarters, Baltimore.
The Department of Washington and the Department of Northeastern Virginia, will constitute a geographical Division under Major General McClellan, U.S.A., Headquarters, Washington.
L. THOMAS, Adjutant General