SS William S. Ladd (MC hull number 2084) was an American Liberty ship built during World War II, one of the 2,710 type 'EC2-S-C1' ships that carried all kinds and types of dry cargo during the war. She was named for William S. Ladd, an American politician and businessman in Oregon, who twice served as Portland's mayor in the 1850s. The ship's keel was laid on August 29, 1943, and 15 days later, on September 13, the hull was launched. William S. Ladd was fitted out in seven days, and was delivered to the U.S. Navy on September 20. The Navy placed Ladd under charter to Weyerhaeuser Steamship Co.