A CO. 1st BN 21st Inf.

A Company, 1st Battalion, 21st Infantry Regiment ("A CO, 1-21 IN"), traces its lineage to the original 21st Infantry Regiment, constituted in 1861. The unit has served with distinction in major conflicts including the Indian Wars, World War II, the Korean War, and the Vietnam War, earning numerous campaign streamers and unit citations. During the Vietnam War, A Company was engaged in intense combat operations as part of the 11th Infantry Brigade, Americal Division. In recent decades, the unit has continued its legacy as part of the 25th Infantry Division, participating in operations in the Pacific and supporting missions in the Global War on Terrorism.