Originally the company had been a foundry powered by a horse, but they bought their first steam engine in 1842 and were soon making engines themselves. A leading producer of Corliss steam engines in the 19th century, they switched in the early 20th century to making compressors, and became Cooper-Bessemer Corporation in a 1929 merger, before continuing diversification led to the Cooper Industries name being adopted in 1965.
In 1967 the company entered the hand tool business by acquiring Lufkin Rule, a maker of measuring instruments, and subsequently added a large number of other hand tool businesses. In the 1970s they entered aircraft maintenance, but subsequently sold off Cooper Airmotive. In 1979 they bought Gardner-Denver Company, their largest acquisition up to that point, extending their range of products serving the energy industry, which had been a key market since they started making compressors and a catalyst for their move of corporate headquarters to Houston in 1967.
The acquisitions of Crouse-Hinds Company in 1980 and McGraw-Edison in 1985, as well as the buyout of Westinghouse's lighting division in 1982, made electrical products the largest part of the company, which has remained the case ever since. McGraw-Edison had been the legal successor to the old Studebaker and Packard auto companies and had some auto parts operations, and Cooper made additional acquisitions in that area including Moog Automotive and Champion Spark Plug, but ultimately sold its automotive operations to Federal-Mogul.
In the 1990s first Gardner-Denver was spun off and then the entire remaining Petroleum & Industrial Equipment segment was separated out as Cooper Cameron Corporation, including all remaining product lines from the company's...