 Hubbard 's first military service was with the Montana Army National Guard , which he joined at the age of 16 in October 1927 while still at school , falsely stating that his age was 18 . Enlisting at the State Armory in his home town of Helena , Montana , he served as a private in the Headquarters Company of 163rd Infantry . In May 1930 , at the age of 19 , he joined the Marine Corps Reserve 20th Regiment , a training unit connected with George Washington University where he was a student from 1930 – 32 . 
