The regiment was organized during the summer of 1861 by James A. Tait, who served as the unit’s first colonel.
When Union forces in the Shenandoah region were consolidated into the Army of Virginia, the 1st D.C. Infantry became part of the 2nd Division, II Corps.
Following the campaign, the regiment was reassigned to the defenses of Washington, where it served for the remainder of the war.
At first, it was part of the XII Corps of the Army of the Potomac, but was transferred to the Department of Washington.
On February 28, 1865, the regiment was consolidated with the 2nd District of Columbia Infantry.