Ministry of Supply

The Ministry of Supply (MoS) was a department of the UK government formed on 1 August 1939 by the Ministry of Supply Act 1939 (2 & 3 Geo. 6. c. 38) to co-ordinate the supply of equipment to all three British armed forces, headed by the Minister of Supply. A separate ministry, however, was responsible for aircraft production, and the Admiralty retained responsibilities for supplying the Royal Navy. During the war years the MoS was based at Shell Mex House in The Strand, London. The Ministry of Supply also took over all army research establishments in 1939. The Ministry of Aircraft Production was abolished in 1946, and the MoS took over its responsibilities for aircraft, including the associated research establishments. In the same year, it also took on increased responsibilities for atomic weapons, including the H-bomb development programme. The Ministry of Supply was abolished in late 1959 and its responsibilities passed to the Ministry of Aviation, the War Office, and the Air Ministry. The latter two ministries were subsequently merged with the Admiralty to form the Ministry of Defence. The Ministry of Supply instigated the Rainbow Codes designation system. This assigned projects a two-word codename, the first word being a colour and the second a noun. As a result, secret weapon projects—including numerous nuclear weapons—were given lighthearted names such as Green Cheese, Blue Slug or Red Duster.