Ten P2-SE2-R1 ships were ordered by the Maritime Commission in World War II.

In 1946 the ships were all decommissioned by the navy and transferred back to the Maritime Commission, and from there to the United States Army.

Eleven P2-S2-R2 ships were ordered by the Maritime Commission in World War II.

The ships were laid down by Federal Shipbuilding and Dry Dock Company of Kearny, New Jersey.

Five were retained by the Navy and were transferred to the Military Sea Transportation Service in October 1949 to be manned by civilian crews, and two others were transferred to American President Lines with the intent of being converted to a passenger liners, but ended up being chartered troop ships that in the Korean War were rejoined to military control as part of the Military Sea Transportation Service.