Doyen was launched as transport AP-2 on 9 July 1942 by Consolidated Steel of Los Angeles, California, under a Maritime Commission contract; sponsored by Miss F. D. Johnson, granddaughter of BGen Doyen; reclassified APA-1, 1 February 1943; acquired by the Navy 20 April 1943 and converted at Bethlehem Steel of San Pedro, California; and commissioned 22 May 1943.

After bringing her passengers to Pearl Harbor, Doyen returned to the west coast for training duty, arriving at San Diego on 18 December.

Doyen got underway 13 January 1944 for the invasion of Kwajalein, landing her troops the last day of the month and receiving casualties and prisoners of war for transportation to Pearl Harbor where she arrived on 15 February.

She remained in the Hawaiian Islands on training duty until 30 May when she sailed for Eniwetok thence to the invasion of Saipan from 16 to 22 June and Guam from 22 to 28 July.

Doyen was laid up in the National Defense Reserve Fleet until transferred to the Massachusetts Maritime Academy in 1959, which renamed her TS Bay State II.