The 205th Infantry Brigade, was first formed as part of the United States Army Reserve's 103rd Division. It was active from 1921 to 1942 and then from 1963 through 1994, and then reformed in 2006. It was initially formed within the Organized Reserve Corps in Arizona and New Mexico, including the 409th and 410th Regiments. Its sister brigade within the 103rd Division was the 206th Brigade in Colorado, which included the 411th and 412th Regiments.