The training center was first opened on June 1, 1942, with accommodations for 900 men. It was solely to train recruits. Specialty training was added later to include fireman, signalman, laundryman, radioman, boatswain's mate, cooks. and bakers, and port security. After the war, Government Island remained a Coast Guard Training Center with the addition of the Weather Bureau, Internal Auditors, and the Bureau of Roads. During the late 1960s, the Training & Supply Center was the Coast Guard's largest field unit on the West Coast.
The Training Center graduated 60-100 seaman apprentices and fireman apprentices each week. The Supply Center provided support to the western area districts including Squadron One and Squadron Three in Vietnam. The cutters Taney, Gresham, and Barataria were home-ported on the island at the time.
