The ships were capable of a top speed of 19 knots (35 km/h; 22 mph), and due to their origin as tankers, had extensive fuel storage.

In 1941, as United States participation in World War II became increasingly likely, the US Navy embarked on a construction program for escort carriers, which were converted from transport ships of various types.

These proved to be very successful ships, and the Commencement Bay class, authorized for Fiscal Year 1944, were an improved version of the Sangamon design.

[1] They proved to be the most successful of the escort carriers, and the only class to be retained in active service after the war, since they were large enough to operate newer aircraft.

Given the very large storage capacity for oil, the ships of the Commencement Bay class could steam for some 23,900 nautical miles (44,300 km; 27,500 mi) at a speed of 15 knots (28 km/h; 17 mph).

[2] The first ship of the class was laid down on 23 September 1943 at the Todd Pacific Shipyards in Tacoma, Washington, originally under the name St. Joseph Bay.

She operated in this role in Puget Sound for the next nine months, during which time she trained some 545 officers and 5,053 enlisted men who went on to serve aboard Commencement Bay's sister ships as they were completed at the Todd Pacific facilities.

[6] Over the course of the following months, Commencement Bay sailed south to visit Los Angeles and San Pedro, California, before returning to Tacoma on 28 January.