The origins of GKN lie in the founding of the Dowlais Ironworks, by landowner Wyndham William Lewis. John Guest was appointed manager of the works in 1767. He discovered coal on Lewis's property and used it to replace charcoal for smelting. On 9th July 1900, the Dowlais Iron Company and Arthur Keen's Patent Nut and Bolt Company merged to form Guest, Keen & Co. Ltd. Nettlefolds Limited, a leading manuacturer of fasteners, had been established in Smethwick in 1854 and was acquired in 1902 leading to the change of name to Guest, Keen and Nettlefolds.

These mergers heralded half a century in which the name GKN became synonymous with the manufacture of screws, nuts, bolts and other fasteners. The company reflected the vertical integration fashionable at the time embracing activities from coal and ore extraction, and iron and steel making to manufacturing finished goods.