 After being mustered into service for eight months along the Mexican border in 1916, it was briefly mustered out of service for less than a month only to be mustered back into Federal service on 10 April 1917.After being federalized it was redesignated as the 150th Infantry Regiment and assigned to the 38th Division on 19 September 1917.The regiment would remain assigned to the 38th Division until the beginning of World War II.