 First Army Division East was activated at Fort Meade, Maryland.First Army Division West was activated on 7 March 2007, at Fort Carson, Colorado, and was transferred to its current headquarters at Fort Hood, Texas as part of the 4th Infantry Division realignment.First Army Division West was established by the Department of the Army to provide training and readiness oversight and mobilization operations for an area of responsibility spanning the states and territories west of the Mississippi River.