Designations
Prior to 1941, only cavalry divisions were specifically designated; infantry divisions were simply designated by "Division". Following the advent of the armored division, infantry divisions became officially designated by "Infantry Division" (with the 25th Infantry Division being the first constituted by the adjutant general as such). All of the 1917–1941 (non-cavalry) divisions, with the exceptions of the 10th through 20th and 101st Divisions, would be redesignated as Infantry Divisions at some point in the 1941–present era.
Other than the aforementioned Armored, Cavalry, and Infantry, the only official Army division designations are Air Assault (one test division), Airborne, Light (three test divisions in World War II), Motorized (briefly authorized from 1942 to 1943), and Mountain. For lineage purposes, the 101st Airborne Division maintains its designation as an airborne division, though it is currently organized as an air assault division.
Divisions listed with an additional identifier in parentheses ("alpine" or "test", for example) existed only with that identifier. Divisions that have held multiple additional identifiers, such as the 1st Cavalry ("airmobile", "heavy") and the 9th Infantry ("light", "motorized"), are left unidentified, regardless of their current additional identifier.
An unspecified division today refers to a United States Army Reserve training division.
- (*) denotes divisions that reorganized under a different division designation while still active
- Bold denotes current United States Army divisions
Read more about this topic: Divisions Of The United States Army