After President Franklin D. Roosevelt declared a national emergency in September 1939, the country had a need to produce ordnance materials for national defense. The Secretary of the Navy selected Chicagoland, specifically the former Harlem Race Track / Harlem Golf Course at Roosevelt Road from Hannah Avenue to Des Plaines Avenue as the location. The U.S. Naval Ordnance Plant, known as Ameritorp, would produce torpedoes, mainly the Mark 13 and Mark 15, as well as spare parts and tools.
By 1943, Ameritorp employed over 6,000 people, both men and women (making it one of the largest employers in Illinois). The plant was managed by the private company, the American Can Company, until 1945 when the contractor-operated facility switched to a Navy operated facility.
Production of torpedoes drastically declined by 1964, and the name of the plant was changed to Naval Ordnance Station. The station closed in 1970 and was converted into the Forest Park Mall.