In 1921 the formation of the National Guard 21st through 24th Cavalry Divisions began with the First, Second, and Third Army Areas supporting the 21st, 22nd, and 24th, respectively. The 23d was the nation's at-large cavalry division, supported by all army areas (Alabama, Massachusetts, New Mexico, North Carolina, Tennessee, Texas, and Wisconsin Army National Guards). In a short time the divisions had the prescribed cavalry regiments and machine gun squadrons but not the majority of their support organizations. To create the Organized Reserve cavalry divisions, the War Department added the 61st, 62nd; 63rd; 64th, 65th and 66th Cavalry Divisions to the rolls of the Army on 15 October 1921.