James Nasmyth (1808-1890) founded the original company in 1836 at the Bridgewater Foundry. They originally made special purpose machine tools, steam engines and other engineering products. In particular they produced Nasmyth’s own invention of the steam hammer, which revolutionised practice in heavy engineering. The company was known as Nasmyth Gaskell & Company from 1838 to 1850, following investment by Holbrook Gaskell. From 1850 it was known as James Nasmyth & Company until Nasmyth retired in 1856. In 1857 the company became the Patricroft Iron Works. In 1867 Robert Wilson joined the works and the company changed its name again, first to Nasmyth Wilson & Company and finally in 1882 to Nasmyth Wilson & Co Ltd. Until the 1880s locomotive building was neither a major nor a consistent part of the company’s production, but increased from that decade. Most of the production was for railway companies abroad. Orders became difficult to obtain after the First World War and in 1939 the company was wound up. The works were taken over by the Ministry of Supply in that year as the Patricroft Royal Ordnance Factory. They built some 1,531 locomotives between 1839 and 1939.

Formerly constituted in January 1947 with responsibility for the inter-relations of the three armed services and their supply. On 1 April 1964 a unified Ministry of Defence under a single Secretary of State absorbed the Admiralty, War Office and Air Ministry. In 1971 the defence functions of the Ministry of Aviation Supply were absorbed when the MoD took over responsibility for supplying military aircraft and guided weapons.