"Ransom" was laid down 24 April 1943 by General Engineering & Dry Dock Co., San Francisco, California; launched 18 September 1943; sponsored by Mrs. Dwight H. Dexter and commissioned 5 August 1944, Lt. Comdr. William N. McMillen, USNR, in command. After shakedown off the California coast, "Ransom" got underway for Hawaii 15 October and arrived at Pearl Harbor a week later for escort duty back to the west coast and later to Eniwetok, Ulithi, and Kossol Roads, arriving at the latter 12 January 1945. She then worked in the antisubmarine patrol screen off Peleliu.