Operating out of Norfolk, Virginia, General W. A. Mann delivered troops and supplies to the North African theater, making four successive round-trip voyages to Casablanca and one to Oran before mid-May 1944.

Eleven days later she sailed for Bombay, India, via Gibraltar, Algiers and the Suez Canal and returned to the west coast of the United States via Brisbane, Australia, and New Guinea, thence to San Pedro, California, arriving 13 January 1945.

From 2 November 1945 to 5 January 1946 she made a round trip voyage from Seattle to Nagasaki and Wakayama, Japan, setting the pattern of a series of "Magic Carpet" passages and "Diaper Runs" in which servicemen and their families were carried to and from the Far East.

From this latter port, she returned to New York and thence steamed back to Bremerhaven via Dover as before, getting underway for Morocco, Suez, Colombo, Indochina, and finally to San Francisco 22 September 1951 via Guam and Hawaii.

From 1952 to 1962 General W. A. Mann made frequent trans-Pacific runs to Japan, Korea, Okinawa, Guam, the Philippines, and Taiwan out of west coast ports, and occasional passages to Alaska.