The union played a major role in the liberal wing of the Democratic Party under the leadership of Walter Reuther (president 1946–1970).

It was known for gaining high wages and pensions for automotive manufacturing workers, but it was unable to unionize auto plants built by foreign-based car makers in the South after the 1970s, and it went into a steady decline in membership; reasons for this included increased automation, decreased use of labor, mismanagement, movements of manufacturing (including reaction to NAFTA), and increased globalization.

[2] For most of its history, the American Federation of Labor (AFL) had only focused on organizing skilled workers practicing specific trades, an approach known as craft unionism.

[9] After the Toledo local led an unauthorized but successful strike against General Motors (GM), the AFL caved to pressure and called for a convention.

Militant local unions quickly managed to overturn that situation, and the struggle alienated the UAW from the AFL leadership.

The union found rapid success with the sitdown strike, a tactic where workers "sit down" at their work stations to occupy a factory.

[14] Sitdown strikes enabled small numbers of workers to interrupt the assembly line and stop production across an entire plant.

By January 25, strikes and the effects of production shutdowns idled 150,000 workers at fifty General Motors plants from California to New York.

By mid-1937 the new union claimed 150,000 members and was spreading through the auto and parts manufacturing towns of Michigan, Ohio, Indiana, and Illinois.

At the Battle of the Overpass, Ford Service Department personnel beat union organizers in front of news photographers.

Older Black workers felt loyalty to Henry Ford because he had hired and paid them well at a time when other auto companies would not.

The UAW extracted a better deal from Ford than from other automakers, including pay increases, a closed shop, and rehiring of pro-union workers.

[23] The agreement also included a non-discrimination clause drafted by Shelton Tappes, a Black foundryman who had served on the UAW negotiating team.

[citation needed] Walter Reuther won the election for president at the UAW's constitutional convention in 1946 and served until his death in an airplane accident in May 1970.

Reuther would pick one of the Big Three automakers (General Motors, Ford, and Chrysler), and if it did not offer concessions, he would strike it and let the other two absorb its sales.

The UAW disaffiliated from the AFL–CIO on July 1, 1968, after Reuther and AFL–CIO President George Meany could not come to agreement on a wide range of policy issues or reforms to AFL–CIO governance.

[33] On July 24, 1968, just days after the UAW disaffiliation, Teamsters General President Frank Fitzsimmons and Reuther formed the Alliance for Labor Action as a new national trade union center to organize unorganized workers and pursue leftist political and social projects.

[25] The UAW became strongly anti-communist after it expelled its Communist leaders in the late 1940s following the Taft–Hartley Act, and supported the Vietnam War and opposed the antiwar Democratic candidates.

At the same time, it used this rhetoric to simultaneously rebuff the demands and limit the organizing efforts of Black workers seeking to overcome institutional racial hierarchies in the workplace, housing, and the UAW.

UAW workers receiving generous benefit packages when compared with those working at non-union Japanese auto assembly plants in the U.S., had been cited as a primary reason for the cost differential before the 2009 restructuring.

[44] The UAW asserts that most of this labor cost disparity comes from legacy pension and healthcare benefits to retired members, of which the Japanese automakers have none.

[52] The Big Three also based their respective market strategies on fuel-inefficient SUVs, and suffered from lower quality perception (vis-a-vis automobiles manufactured by Japanese or European car makers).

In 2010, Bob King hired Richard Bensinger to organize Japanese, Korean, and German transplant factories in the United States.

[62] In March 2020, the Detroit United Auto Workers union announced that after discussion with the leaders of General Motors, Ford, and Fiat Chrysler Automobiles, the carmakers would partially shut down factories on a "rotating" basis to combat the COVID-19 pandemic.

[64] A corruption probe by the Justice Department against UAW and 3 Fiat Chrysler executives was conducted during 2020 regarding several charges such as racketeering, embezzlement, and tax evasion.

[65][66][67] It resulted in convictions of 12 union officials and 3 Fiat Chrysler executives, including two former Union Presidents, UAW paying back over $15 million in improper chargebacks to worker training centers, payment of $1.5 million to the IRS to settle tax issues, commitment to independent oversight for six years, and a referendum that reformed the election mode for leadership.

[74] After the success of the strike, in November 2023, the UAW announced that it was launching a simultaneous campaign to unionize 150,000 workers at other automakers with plants in the United States: BMW, Honda, Hyundai, Lucid, Mazda, Mercedes, Nissan, Rivian, Subaru, Tesla, Toyota, Volkswagen, and Volvo.

[75][76] In April 2024, after two failed attempts, 73% of workers at the Volkswagen (VW) Chattanooga, Tennessee plant voted to join the UAW,[3][77][78] the union's first victory in the South outside Detroit's Big Three.

[79] District 65, a former affiliate of the Retail, Wholesale and Department Store Union that included as a predecessor the United Office and Professional Workers of America, merged into the UAW in 1989.