Before he was accepted to the United States Military Academy at West Point, New York, he was already in his second year at Purdue University.

[4] In the 1950s, Montague worked for the Defense Department and Atomic Energy Commission during these agencies' development of nuclear warheads.

[4] When he was a colonel, Montague became part of Ambassador Robert W. Komer's personal staff during the latter's administration of the Civil Operations and Revolutionary Development Support (CORDS) program in Vietnam.

In November 1970, he joined the Special Assistant for the Modern Volunteer Army (SAMVA), where he was noted for his innovations in all-volunteer concept work.

He also became the executive director of Special Olympics International, which oversaw a $150 million sports program for mentally retarded persons.