The original Hummers were designed by AM General Corporation, a wholly owned subsidiary of American Motors Corporation (AMC), and were built at their Mishawak aassembly plant in Indiana. The Humvee replaced the military Jeeps that were produced by AMC until 1982.
In 1979, the United States Army was seeking contractors for a new "High Mobility Multi-Purpose Wheeled Vehicle" (HMMWV) which could follow the tracks and ruts of full size army trucks. At that time, General Dynamics, Teledyne, and Chrysler Defense had HMMWV designs under development. Among the four competitors for the contract, AM General designed an entirely new vehicle to meet the Army's requirements. In less than one year, it was the first to deliver a prototype vehicle. Initial production versions were delivered to the Army's proving grounds in April 1982.
After testing was completed AM General was awarded the contract to supply its HMMWV to the United States armed forces. The first models were built in a variety of military-based equipment and versions. The first contract was in 1983, worth US$1.2 billion to produce 55,000 "Humvees" by 1985. The first production vehicle was assembled by AM General on January 2, 1985. The contract was later increased for an additional 15,000 units.
AM General had planned to sell a civilian version of the Humvee as far back as the late 1980s. Having the same structure and most mechanical components, the civilian Hummers were finished in automotive gloss paint, adding passenger car enhancements such as air conditioning, sound insulation, upgraded upholstery, stereo systems, wood trim, and convenience packages. The civilian model began in part because of the persistence of Arnold Schwarzenegger, who saw an Army convoy while filming a movie.
In December 1999, AM General sold the brand name to General Motors, but continued to manufacture the vehicles. GM was responsible for the marketing and distribution of all Hummers produced by AM General. Shortly thereafter, GM introduced two of its own design models, the H2 and H3, and renamed the original vehicle H1. AM General continued to build the H1 until it was discontinued in 2006, and was contracted by GM to produce the H2. The H3 was built in Shreveport, LA alongside the Chevrolet Colorado and GMC Canyon pickups, with which it shared the GMT-355 platform (modified and designated GMT-345). Hummer dealership buildings featured an oversized half Quonset Hut style roof, themed to the Hummer brand's military origins.
By 2006, the Hummer began to be exported and sold through importers and distributors in 33 countries. On October 10, 2006, GM began producing the Hummer H3 at its Port Elizabeth plant in South Africa for international markets. The Hummers built there at first were only left-hand drive, but right-hand drive versions were added and exported to Australia and other markets.
The H2 was also assembled in Kaliningrad, Russia, by Avtotor, starting in 2006 and ending in 2009. The plant produced a few hundred vehicles annually, and its output was limited to local consumption with five dealers in Russia.
On June 3, 2008, one day prior to GM's annual shareholder meeting, Rick Wagoner, GM's CEO at that time, said the brand was being reviewed, and had the possibility of either being sold, having the production line completely redesigned, or being discontinued. This was due to the decreasing demand for large SUVs as a result of higher oil prices. Almost immediately after the announcement, a pair of Indian automakers, including Mahindra & Mahindra, expressed interest in purchasing all or part of Hummer.
On June 1, 2009, as a part of the General Motors bankruptcy announcement, the company revealed that the Hummer brand would be discontinued. However, the following day GM announced that instead it had reached a deal to sell the brand to an undisclosed buyer. After GM announced that same day that the sale was to an undisclosed Chinese company, CNN and the New York Times identified the buyer of the Hummer truck unit as China-based Sichuan Tengzhong Heavy Industrial Machinery Company Ltd.Later that day, Sichuan Tengzhong itself announced the deal on their own website.
On January 6, 2010, GM CEO Ed Whitacre said he hoped to close the deal with Tengzhong by the end of that month. On February 1, 2010, it was announced that Sichuan and General Motors had agreed to extend the deadline until the end of February as Sichuan tried to get approval by the Chinese government. It was also revealed that the price tag of the Hummer brand was $150 million.
Later, on February 24, 2010, GM announced the Tengzhong deal had collapsed and the Hummer brand would soon shut down. There were reports that Sichuan Tengzhong might pursue the purchase of the Hummer brand from GM by purchasing it privately through the company's new J&A Tengzhong Fund SPC, a private equity investment fund owned by an offshore entity that was recruiting private investors to buy into its acquisition plan. The financial markets posed problems for established borrowers and even more for Tengzhong, a little-known company from western China, at the same time as the potential value of the Hummer brand continued to decline given high fuel prices and weak consumer demand.
The company announced it was willing to consider offers for all or part of the assets. American company Raser Technologies along with several others expressed interest in buying the company. However, on April 7, 2010, this attempt failed as well, and General Motors officially said it was shutting down the Hummer SUV brand and offering rich rebates in a bid to move the remaining 2,200 vehicles.