North American federation of labor unions from 1935 to 1955
The Congress of Industrial Organizations (CIO) was a federation of unions that organized workers in industrial unions in the United States and Canada from 1935 to 1955. Originally created in 1935 as a committee within the American Federation of Labor (AFL) by John L. Lewis, a leader of the United Mine Workers (UMW), and called the Committee for Industrial Organization. Its name was changed in 1938 when it broke away from the AFL. It focused on organizing unskilled workers, who had been ignored by most of the AFL unions.
The CIO supported Franklin D. Roosevelt and his New Deal coalition, and membership in it was open to African Americans. CIO members voted for Roosevelt overwhelmingly.
Both the CIO and its rival the AFL grew rapidly during the Great Depression. The rivalry for dominance was bitter and sometimes it was violent.
In its statement of purpose, the CIO said that it had formed to encourage the AFL to organize workers in mass production industries along industrial union lines. The CIO failed to change AFL policy from within. On September 10, 1936, the AFL suspended all 10 CIO unions (two more CIO unions had joined the AFL during the previous year). In 1938, these unions formed the Congress of Industrial Organizations as a rival labor federation. 
Section 504 of the Taft–Hartley Act of 1947 required union leaders to swear that they were not Communists, which some CIO leaders refused to do; they were expelled. In 1955, the CIO rejoined the AFL, forming the new entity known as the American Federation of Labor and Congress of Industrial Organizations (AFL–CIO).
Background.
The CIO was born out of a fundamental dispute within the United States labor movement over whether and how to organize industrial workers. The eight union chiefs who founded the CIO were not happy with how the AFL was unwilling to work with America's manufacturing combines. Those who favored craft unionism believed the most effective way to represent workers was to defend the advantages they had secured through their skills. They focused on the hiring of skilled workers, such as carpenters, lithographers, and railroad engineers in an attempt to maintain as much control as possible over the work their members did by enforcement of work rules, zealous defense of their jurisdiction to certain types of work, control over apprenticeship programs, and exclusion of less-skilled workers from membership.
Craft unionists were opposed to organizing workers on an industrial basis, into unions which represented all of the production workers in a particular enterprise, rather than in separate units divided along craft lines.
The proponents of industrial unionism, on the other hand, generally believed that craft distinctions may have been appropriate in those industries in which craft unions had flourished, such as construction or printing, but they were unworkable in industries such as steel or auto production. In their view, dividing workers in a single plant into a number of different crafts represented by separate organizations, each with its own agenda, would weaken the workers' bargaining power and leave the majority, who had few traditional craft skills, completely unrepresented.
While the AFL had always included a number of industrial unions, such as the United Mine Workers and the Brewery Workers, the most dogmatic craft unionists had a stronghold on power within the federation by the 1930s. They used that power to quash any drive toward industrial organizing.
Industrial unionism became even more fierce in the 1930s, when the Great Depression in the United States caused large membership drops in some unions, such as the United Mine Workers and the International Ladies' Garment Workers' Union. A number of labor leaders, particularly John L. Lewis of the United Mine Workers, came to the conclusion that their own unions would not survive while the great majority of workers in basic industry remained nonunion. They started to press the AFL to change its policies in this area.
The AFL, in fact, responded and added even more new members than the CIO. The AFL had long permitted the formation of "federal" unions, which were affiliated directly with the AFL; in 1933, it proposed to use them to organize workers on an industrial basis. The AFL did not, however, promise to allow the unions to maintain a separate identity indefinitely. That meant the unions might be broken up later to distribute their members among the craft unions that claimed jurisdiction over their work. The AFL, in fact, dissolved hundreds of federal unions in late 1934 and early 1935.
While the bureaucratic leadership of the AFL was unable to win strikes, three victorious strikes suddenly exploded onto the scene in 1934. These were the Minneapolis Teamsters Strike of 1934, the leadership of which included some members of the Trotskyist Communist League of America; the 1934 West Coast Longshore Strike, the leadership of which included some members of the Communist Party USA; and the 1934 Toledo Auto-Lite strike, which was led by the American Workers Party. Victorious industrial unions with militant leaderships were the catalyst that brought about the rise of the CIO.
The AFL authorized organizing drives in the automobile, rubber, and steel industries at its convention in 1934 but gave little financial support or effective leadership to those unions. The AFL's timidity succeeded only in making it less credible among the workers that it was supposedly trying to organize. That was especially significant in those industries, such as auto and rubber, in which workers had already achieved some organizing success, at great personal risk.
The dispute came to a head at the AFL's convention in Atlantic City in 1935. On October 19, the closing day of the convention, William Hutcheson, the President of the United Carpenters, made a slighting comment about a rubber worker who was delivering an organizing report. Lewis responded that Hutcheson's comment was "small potatoes," and the Hutcheson replied, "I was raised on small potatoes, that is why I am so small." After some more words, during which Hutcheson called Lewis a "vile name", Lewis punched Hutcheson. The two men collapsed a table and fell on the floor, throwing punches. The incident helped cement Lewis's image in the public eye as someone willing to fight for workers' right to organize.
History.
The standard scholarly history by Robert Ziegler provides the historical details.
Founding.
Shortly afterward, Lewis called together Charles Howard, President of the International Typographical Union; Sidney Hillman, head of the Amalgamated Clothing Workers of America; David Dubinsky, President of the ILGWU, Thomas McMahon, head of the United Textile Workers; John Sheridan of the Mine, Mill and Smelter Workers Union; Harvey Fremming, of the Oil Workers Union; and Max Zaritsky, of the Hatters, Cap and Millinery Workers. They discussed the formation of a new group within the AFL to carry on the fight for industrial organizing. The creation of the Committee for Industrial Organization was announced on November 9, 1935.
Whether Lewis then intended to split the AFL over this issue is debatable; at the outset, the CIO presented itself as only a group of unions within the AFL gathered to support industrial unionism, rather than a group opposed to the AFL itself.
The AFL leadership, however, treated the CIO as an enemy from the outset by refusing to deal with it and demanding that it dissolve. The AFL's opposition to the CIO, however, only increased the stature of the CIO and Lewis in the eyes of the industrial workers who were keen on organizing and were disillusioned with the AFL's ineffective performance. Lewis continued to denounce the AFL's policies, and the CIO offered organizing support to workers in the rubber industry who went on strike and formed the Steel Workers Organizing Committee (SWOC) in defiance of all of the craft divisions that the AFL had required in past organizing efforts. In 1936, Lee Pressman, affiliated with the far left, became the union's general counsel until 1948.
The first major industrial union to be chartered by the CIO, on November 16, 1936, was the United Electrical, Radio and Machine Workers of America (UE).
The subsequent explosive growth of the UE was instrumental for the survival in the early days of the CIO. By the end of 1936, the UE had organized the General Electric plant at Schenectady, New York, and the UE went on to organize 358 more local unions with contracts covering over 600,000 workers, at 1375 plants.
Initial triumphs.
The CIO met with dramatic initial successes in 1937, with the UAW winning union recognition at General Motors Corporation after a tumultuous forty-four-day sit-down strike, while the Steel Workers Organizing Committee (SWOC) signed a collective bargaining agreement with U.S. Steel. Those two victories, however, came about very differently.
The CIO's initial strategy was to focus its efforts in the steel industry and then build from there. The UAW, however, did not wait for the CIO to lead it. Instead, having built up a membership of roughly 25,000 workers by gathering in federal unions and some locals from rival unions in the industry, the union decided to go after GM, the largest carmaker of them all, by shutting down its nerve center, the production complex in Flint, Michigan.
The Flint Sit-Down Strike was a risky and illegal enterprise from the outset: the union was able to share its plans with only a few workers because of the danger that spies employed by GM would alert management in time to stop it, yet needed to be able to mobilize enough to seize physical control of GM's factories. The union, in fact, not only took over several GM factories in Flint, including one that made the dies necessary to stamp automotive body parts and a companion facility in Cleveland, Ohio, but held on to those sites despite repeated attempts by the police and National Guard to retake them and court orders threatening the union with ruinous fines if it did not call off the strike.
While Lewis played a key role in negotiating the one-page agreement that ended the strike with GM's promise to recognize the UAW as the exclusive bargaining representative of its employees for a six months period, UAW activists, rather than CIO staff, led the strike.
The organizing campaign in the steel industry, by contrast, was a top-down affair. Lewis, who had a particular interest in organizing the steel industry because of its important role in the coal industry where UMW members worked, dispatched hundreds of organizers - many of whom were his past political opponents or radicals drawn from the Communist-led unions that had attempted to organize the industry earlier in the 1930s - to sign up members. Lewis was not particularly concerned with the political beliefs of his organizers, so long as he controlled the organization; as he once famously remarked, when asked about the "reds" on the SWOC staff, "Who gets the bird? The hunter or the dog?".
The SWOC signed up thousands of members and absorbed a number of company unions at U.S. Steel and elsewhere, but did not attempt the sort of daring strike that the UAW had pulled off against GM. Instead, Lewis was able to extract a collective bargaining agreement from U.S. Steel, which had previously been an implacable enemy of unions, by pointing to the chaos and loss of business that GM had suffered by fighting the UAW. The agreement provided for union recognition, a modest wage increase and a grievance process. CIO unions signed multiyear contracts, often complicated and long, with GM, U.S. Steel, and other corporations in order to minimize strikes and also make sure employers took care of the work process.
The CIO also won several significant legal battles. "Hague v. Committee for Industrial Organization" 307 U.S. 496 (1939), arose out of events late in 1937. Jersey City, New Jersey Mayor Frank "Boss" Hague had used a city ordinance to prevent labor meetings in public places and stop the distribution of literature pertaining to the CIO's cause. District and circuit courts ruled in favor of the CIO. Hague appealed to the United States Supreme Court, which held in 1939 that Hague's ban on political meetings violated the First Amendment right to freedom of assembly.
Early setbacks and successes.
The UAW was able to capitalize on its stunning victory over GM by winning recognition at Chrysler and smaller manufacturers. It then focused its organizing efforts on Ford, sometimes battling company security forces as at the Battle of the Overpass on May 26, 1937.
At the same time, the UAW