LST-222 was laid down on 16 March 1943 at Seneca, III., by the Chicago Bridge & Iron Co.; launched on 17 August 1943; sponsored by Mrs. Ruth Clydedale; and commissioned on 10 September 1943.
During World War II, LST-222 was assigned to the Asiatic-Pacific theater and participated in the following operations:
Occupation of Kwajalein and Majuro Atolls—January and February 1944
Capture and occupation of Saipan—June and July1944
Tinian capture and occupation—July 1944
Capture and occupation of southern Palau Islands—September and October 1944
Following the war, LST-222 was redesignated LSTH-222 on 15 September 1945. She performed occupation duty in the Far East until early February 1946 and served with the Military Sea Transportation Service as T-LST-222 from 31 March 1952 to 15 July 1972. On 15 July 1972, the tank landing ship was transferred to the Philippines as a loan, where, as of 1 January 1979, she remained active as Mindoro Occidental (LT-93).
LST-222 earned four battle stars for World War II service.