Eaton Corporation Plc is a multinational power management company with 2016 sales of $19.7 billion, founded in the United States with corporate headquarters in Dublin, Ireland. Eaton has approximately 95,000 employees and sells products to customers in more than 175 countries.

In 1911, Joseph O. Eaton, brother-in-law Henning O. Taube and Viggo V. Torbensen, incorporated the Torbensen Gear and Axle Co. in Bloomfield, New Jersey. With financial backing from Torbensen's mother, the company was set to manufacture Torbensen's patented internal-gear truck axle. In 1914, the company moved to Cleveland, Ohio, to be closer to its core business, the automotive industry.

The Torbensen Axle Company incorporated in Ohio in 1916, succeeding the New Jersey corporation. A year later, Republic Motor Truck Company, Torbensen's largest customer bought out the company. But Eaton and Torbensen were not content and bowed out of Republic to form the Eaton Axle Company in 1919. A year later, in 1920, Eaton Axle Company merged with Standard Parts. Standard Parts went in receivership later the same year and was later liquidated. In 1923, Eaton bought the Torbensen Axle Co. back from Republic and changed the name to the Eaton Axle and Spring Company.

Eaton officers believed the quickest way to grow the business was through acquisitions and began buying companies in the automotive industry. By 1932, the diversified company changed its name to Eaton Manufacturing Company. In 1937, Eaton became international by opening a manufacturing plant in Canada. In 1958 Eaton Corporation acquired Fuller Manufacturing. The company name changed once again in 1965 to Eaton Yale & Towne Inc. after the acquisition of Yale & Towne Manufacturing Co. in 1963. Stockholders approved the change to the company's current name in 1971. In 1978, Eaton Corporation acquired Samuel Moore & Company, Kenway Systems, and Cutler-Hammer.

Eaton's business comprises two sectors: Electrical and Industrial:

The electrical sector's products include circuit breakers, switchgear, UPS systems, power distribution units, panelboards, loadcenters, motor controls, meters, sensors, relays and inverters. The main markets for the Electrical Americas and Electrical Rest of World segments are industrial, institutional, government, utility, commercial, residential, information technology and original equipment manufacturer customers.

Eaton is a manufacturer of systems and components for use in mobile and industrial applications. Markets include agriculture, construction, mining, forestry, utility, material handling, machine tools, molding, power generation, primary metals, and oil and gas. The Hydraulics group also includes Eaton's Filtration, Golf Grip and Airflex industrial clutch and brake businesses.

For the aerospace industry, Eaton manufactures and markets a line of systems and components for hydraulic, fuel, motion control, pneumatic systems and engines.

The Vehicle Group comprises the company's truck and automotive segments.

The truck segment is involved in the design, manufacture and marketing of powertrain systems and other components for commercial vehicle markets. Key products include manual and automated transmissions, clutches and hybrid power.

Eaton’s automotive segment produces products such as superchargers, engine valves, valve train components, cylinder heads, locking and limited-slip differentials, fuel, emissions, and safety controls, transmission and engine controls, spoilers, exterior moldings, plastic components, and fluid connectors.

Eaton Electrical purchased the Westinghouse Distribution and Controls Business Unit in 1994 which was one of Eaton's largest acquisitions. The acquisition included all of the Westinghouse electrical distribution and control product business and also included stipulations that the Westinghouse name cannot be used by anyone else on these types of products for years. Today, Eaton Electrical manufactures electrical distribution and control products branded "Eaton" or "Cutler-Hammer" which can replace Westinghouse products in commercial and industrial applications.

Eaton spun off its semiconductor manufacturing equipment business as Axcelis Technologies in 2000.

In 2003, Eaton's Electrical Distribution and Control business (formerly known as Cutler-Hammer) acquired the electrical division of Delta plc. This acquisition brought Delta's brands Holec, MEM, Tabula, Bill and Elek under the Eaton nameplate with the previous Westinghouse divisions and gave the company manufacturing facilities to meet IEC standards, one of the steps to become a global company and developing a worldwide standard.

Soon after this acquisition, Eaton entered a joint venture with Caterpillar Inc. and purchased 51% of I & S operations (now known as Intelligent Switchgear Organization, LLC). This was followed in 2004 by the acquisition of Powerware. The Powerware brand is known for the design and production of medium to large Uninterruptible Power System (UPS) devices. After several years of co-branding UPS products "Eaton|Powerware" the company is switching to the single brand Eaton for all UPS products including; BladeUPS, 9355, 9390, 9395, and 9E.

In 2006, Eaton entered the data center power distribution market. Initial products were internally developed PDU's and RPP's under the Powerware brand and included the PowerXpert metering system. A Powerware brand Static Transfer Switch was added to the portfolio through a brand-label relationship with Cyberex. To complete the power distribution portfolio Eaton released a line of rack power distribution products under its Powerware brand called ePDU. It acquired Aphel Technologies Ltd., a manufacturer of power distribution product for data centers based in Coventry, UK. Shortly after, it added Pulizzi Engineering Inc., Santa Ana, CA-based manufacturer of mission critical power distribution. In late 2007, it acquired the MGE Office Protection Systems division of Schneider Electric, as a result of Schneider's acquisition of APC. A Taiwanese manufacturer, Phoenixtec, was also acquired giving the company the highest share in the Chinese single-phase UPS market.

On May 21, 2012 Eaton announced that they had agreed to purchase Ireland-based Cooper Industries in a cash-and-stock deal valued at about $11.46 billion. The new company is called Eaton Corporation plc and is incorporated in Ireland. Then-Eaton Chairman and CEO Alexander Cutler headed the new corporation. Cooper shareholders received $39.15 in cash and 0.77479 of a share in the newly created company for each Cooper share held. This is worth $72 per share based on Eaton’s closing share price of $42.40 on May 18, 2012, and is 29% above Cooper’s closing stock price. Eaton Corporation plc completed its acquisition of Cooper Industries on Nov 30, 2012. The $13 billion acquisition of Cooper (USD$5.4B Sales revenue -2011), became the largest in Eaton's (USD$16B Sales Revenue-2011) 101-year history.

From 1920s-1964 Eaton was based on East 140th Street. In 1964, Eaton moved its headquarters into the new Erieview Tower where it remained until 1983. In that year, Eaton Corporation moved into a 28-story Cleveland office tower which was renamed for it. Eaton relocated to its new 580,000 square foot facility, named Eaton Center, in Beachwood, Ohio in early 2013. The reincorporation in Ireland as part of the Cooper merger involved establishing a registered head office in Dublin, Ireland but operational headquarters remain in Ohio.

Eaton was selected in 2008 as a recipient of the CALSTART Blue Sky Award with recognition for its environmentally "green" transportation investments, products and actions. The award was directed towards the company's efforts to pioneer heavy duty hybrid-drive technology for trucks. The annual awards recognize outstanding marketplace contributions to clean air, energy efficiency and to the clean transportation industry overall by companies, organizations and individuals.

Operations of Eaton involve the use and disposal of certain substances regulated under environmental protection laws. Eaton continues to modify certain processes on an ongoing, regular basis to reduce the impact on the environment, including the reduction or elimination of certain chemicals used in, and wastes generated from, operations. Eaton has set standards for itself in the category of environmental protection vowing to reduce its own greenhouse gas emissions by 18 percent by 2012.

In 2006, Eaton joined the Green Suppliers Network, a public-private partnership with the EPA and U.S. Department of Commerce, through which small and medium-sized suppliers are helped to develop "lean and clean" manufacturing processes.

Eaton's hybrid electric powertrain combines a diesel engine and electric motor to drive the vehicle.

In 2013, Eaton has been ranked a global leader by Carbon Disclosure Project (CDP) and was named to the Climate Disclosure Leadership Index. Eaton’s position in the index ranked it first among its global competitors in the industrials sector.

Recognitions include the following:

The History of Eaton Corporation 1911–1985
Securities and Exchange Commission