In July 1866, the U.S. Congress had authorized the expansion of the U.S. Army's cavalry arm from six regular regiments to ten. Two of the new regiments were to be white and two were to comprise African-American enlisted men with white officers. One of the new white regiments was the soon to be famous Seventh Cavalry which was organized on this day at Fort Riley in Kansas. Eventually under the command of Colonel Andrew J. Smith, it first policed Reconstruction in the South and then began its extended and fateful service in the Plains Indian Wars. (By John Osborne)