- Constituted 23 July 1918 in the National Army as the 326th Engineers and assigned to the 101st Division
- (101st Division only partially organized October-November 1918; demobilized 11 December 1918; reconstituted 24 June 1921)
- Reconstituted 24 June 1921 in the Organized Reserves as the 326th Engineers and assigned to the 101st Division.
The 326th Engineer Battalion (Air Assault) 'Sapper Eagles' is the only Air Assault Engineer Battalion in the United States Army. The 326th has been a part of the 101st Airborne Division since World War II, and has recently been reflagged under the 20th Engineer Brigade (Combat) (Airborne).