Born in Pelican, Louisiana, Glenn grew up in Shreveport. An art major at Louisiana State University, he had been granted an exemption from service but joined the Navy two weeks after Pearl Harbor. As an ensign, he studied worldwide communications at Harvard University, where he also served on short, sub-chasing cruises. He spent the winter of 1943 on the USS Ruby (PY-2), serving convoy duty to Murmansk. The weather on that trip, he reports, was "six and seven degrees below zero." He was then sent to Providence, Rhode Island, then Groton, Connecticut, and then to Riverside, California. He was shipped to Pearl Harbor where he worked for Captain Hyman Rickover, who eventually became head of nuclear submarines. Assigned to Marine Air Group Twenty-Three, he ordered to Okinawa where he served as a commodore's aide. He lived in a tent through the summer of 1945 and helped censor letters, among other duties. He also served as mess treasurer for 128 men. "We ate goat `til the world looked level," he recalls of the rations, many of which came from Australia. Glenn also saved a man's life, swimming out in a fierce undercurrent to rescue a sailor. Glenn returned to the United States as a lieutenant. After the war he founded Glenn Mason and Associates advertising agency in Shreveport.