Congress of Industrial Organizations CIO

from 1935 to 1955 a labor union organization in the United States structured along industrial lines.

Founded in November 1935, the CIO began as part of the American Federation of Labor (AFL); until 1938 it was called the Committee for Industrial Organization. The organization had approximately 5 million members in 1951. The main role in the battle to form the CIO was played by the leftist trade unions, which were significantly influenced by the Communist Party of the United States. In 1936 the AFL leaders succeeded in excluding from the AFL all labor organizations that supported the committee. In 1938 the committee was reorganized as the Congress of Industrial Organizations, and right-wing labor leaders seized control. In 1949 the CIO left the International Federation of Trade Unions, which it had entered in 1945. In December 1955 a joint meeting of the CIO and the AFL formed the unified AFL-CIO.