She was commissioned with a United States Coast Guard crew in June 1945 and was en route to Marseille on her first operational voyage when the surrender of Japan ended World War II.

Following five trans-Pacific voyages, between October 1946 and January 1947 General J. C. Breckinridge was then converted at Philadelphia for peacetime employment, with special facilities for military dependents.

They were among more than a dozen sighted recently off the Pacific coast and were thought to be remnants of Japanese mine fields torn loose by storms in the Aleutians.

As a ship, operationally subordinate to MSTS she was redesignated T-AP-176, but because she was a commissioned vessel with a Navy, not civilian, crew, General J. C. Breckinridge retained the designation "USS" instead of becoming "USNS."

General J. C. Breckinridge made two more troop voyages in the war in Korea and then returned to regular MSTS transport duty, carrying both military and civilian passengers throughout the Pacific area.

[2] Breckenridge also made at least one other voyage to South Vietnam in 1965, dropping off troops at Cam Ranh Bay and Qui Nhon (and perhaps other ports) from 11 to 17 September.