Robert Earl Cleary was born in Tewksbury, Massachusetts, on 2 June 1931, and graduated from Holyoke Trade High School in May 1949.

Cleary transferred overseas, where he joined the 1st Marine Division in Korea, as a Squad Leader and Right Guide with Company I, 3rd Battalion .

Returning from overseas, he reported to the 1st Rifle Company at the Navy and Marine Corps Reserve Training Center, Springfield, Massachusetts.

In May 1958, he was promoted to staff sergeant, and continued to serve in this assignment until April 1961, when he transferred to Marine Corps Recruit Depot San Diego for duty as a drill instructor.

He returned to San Diego for a short tour as a drill instructor in August 1967, at which time he was selected for promotion to first sergeant.

Upon his return from overseas in May 1973, he was assigned to VMA-223 at Marine Corps Air Station Yuma, where he attained his present grade and served as the Squadron Sergeant Major.

On 1 January 1982, Cleary was selected as the Sergeant Major of Marine Corps Development and Education Command in Quantico, Virginia.