The facility was founded as the Twin Cities Ordinance Plant, set up as a joint venture between the
United States Department of War and the
Federal Cartridge Corporation. In 1941, the Federal Cartridge Corporation won an $87 million contract to build and operate the facility under the
Lend-Lease Act, while ownership would remain with the military. One of six government-owned, contractor-operated small arms ammunition plants set up during World War II under the Lend-Lease Act, the original 100 building complex was completed over a period of six months, and the plant began production in March 1942, with an initial mandate of supplying
.30 Caliber,
.50 Caliber, and
.45 Auto ammunition, later expanded to other types of military equipment. The plant would expand over the next year, consisting of around 300 buildings by 1943. At this time, there were over 20,000 employees at the plant, over half of them women. The plant also employed many African-Americans, at its peak employing around a fifth of the state's black population.
Cecil Newman, a civic leader from Minneapolis, worked alongside Charles L. Horn, then-president of the Federal Cartridge Corporation, to promote the employment and career advancement of African-Americans at the plant during its early years. Newman was eventually given a permanent position as the Director of Negro Personnel at the plant, while Horn was later tapped by President Roosevelt to join the
Fair Employment Practice Committee, a federal committee tasked with assisting the enforcement of
Executive Order 8802, an anti-discrimination order signed by Roosevelt targeting the defense industry. Production also expanded, with components of artillery shells being produced beginning in early 1945. In 1944 it began overhauling old .30- and .50-caliber ammunition by the use of machines that disassembled them into their components. It closed in September, 1945 due to the ending of the fighting in the Pacific. It was reopened on a reserve basis as the Twin Cities Arsenal from 1946 to 1950. The demands of the Korean War restored full production from 1950 until it was closed down in 1957. It was renamed as the Twin Cities Army Ammunition Plant in 1963. The demand for the new 5.56mm NATO and 7.62mm NATO cartridges during the Vietnam War made it reopen briefly from 1965 to 1976. It was in standby from 1976 to 2002 and was finally closed in 2005. ==Future of Site==