The firm was founded by Robert Hawthorn at Forth Banks Works, Newcastle, 1817. Roberts’s brother William became a partner and in 1820 the company became R & W Hawthorn Ltd. Initially the firm concentrated on the building of marine engines, it incorporated locomotives later reportedly after the partners were inspired by witnessing the 1829 Rainhill Trials. In 1831 their first steam locomotive ‘Coronation’ was produced for the Stockton and Darlington Railway. The firm soon became successful as the British railway system expanded rapidly, supplying locomotives to a variety of British railway companies. R & W Hawthorn Ltd. began supplying locomotives to foreign railways in 1838, supplying locomotives to Europe, India, Australia, South America and South Africa. In 1846 a works at Leith was bought for the erection of locomotives that were intended for the Scottish railway; this was to prevent costly transportation by sea. By 1870 over 1,000 locomotives had been built by the company. Robert Hawthorn died in 1867, and in 1870 William Hawthorn retired. The firm was sold for £60, 000 and was acquired by senior partner Benjamin Browne, his principle aide Francis Carr Marshall, William Hawthorn Junior and Joseph Scott. The first intention of the new company was to confine themselves only to marine engines; however they found that their reputation meant that orders for locomotives were easy to secure and decided to continue with production. In 1870 the firm secured the shipyard of Messrs T and W Smith at St Peter’s, Newcastle and all marine engineering was moved away from Forth banks. It was subsequently decided to separate the business activities of the Forth Banks and St Peter’s sites.

In 1886 R and W Hawthorn was amalgamated with the shipbuilding company of Andrew Leslie, thus becoming R and W Hawthorn Leslie & Co. Ltd. In 1937 Robert Stephenson & Co. Ltd purchased the locomotive department of R & W Hawthorn Leslie & Co. Ltd. They became Robert Stephenson and Hawthorns Ltd.

In 1937 Robert Stephenson & Co. Ltd purchased the locomotive department of R & W Hawthorn Leslie & Co. Ltd. They became Robert Stephenson and Hawthorns Ltd. The policy was to concentrate the building of main line locomotives at Robert Stephenson’s Darlington works and industrial locomotives at Forth Banks. In 1944 Vulcan Foundry acquired Robert Stephenson and Hawthorns Ltd, ending Hawthorns' 137 year connection with Forth Banks. In 1955 Vulcan Foundry became full members of the English Electric group of companies, which became part of the GEC group of companies in 1968.