Jose Agosto-Santos was born on February 22, 1945, in Puerto Rico. He enlisted in the U.S. Marine Corps on January 13, 1966, and completed basic training at Paris Island, South Carolina, in April 1966. Pvt Agosto-Santos then attended Rifleman training at Camp Lejeune, North Carolina, from April to June 1966, before deploying to Southeast Asia with Company D, 1st Battalion, 5th Marine Regiment of the 1st Marine Division in South Vietnam from August 1966 until he was captured by the Viet Cong and taken as a Prisoner of War on May 12, 1967. After spending 257 days in captivity, Cpl Agosto-Santos was released by the Viet Cong on January 23, 1968. He was briefly hospitalized at the U.S. Naval Hospital at Bethesda, Maryland, and then received an honorable discharge from the Marine Corps on May 9, 1968.