The American Federation of Labor (established 1886) consisted of skilled craft unions that disagreed with the reform policies and organization of the Knights of Labor. The AFL involved Canadian workers from the beginning, and between 1898 and 1902 the first Canadian organizer, John Flett, chartered over 700 locals. Most Canadian unions were affiliated with the Trades and Labor Congress of Canada, which was associated with, and dominated by, the AFL, especially after the controversial Berlin Decision of 1902 (Union Centrals, National).
During the 1920s the AFL hewed to craft union interests, ignoring unskilled workers in the new mass-production industries (steel, auto, electrical). In November 1935, these workers set up The Committee for Industrial Organization (later known as the Congress of Industrial Organizations, 1937), organizing by industry rather than by craft. The CIO won several spectacular strikes in Canada (see Oshawa Strike), openly engaged in politics and bickered with the AFL.
In 1939 the AFL successfully pressured the TLC to oust the CIO unions from its ranks, leading to the organization of the Canadian Congress of Labour in 1940. New challenges such as automation after WWII persuaded labour leaders in the US to settle their differences and merge in 1955; their Canadian affiliates merged a year later. The AFL-CIO's decline in recent years has reflected the industrial weakness of the traditional blue-collar strongholds of American unionism. Compared to the less than 17% of the American workforce that is organized today, Canadian unionism, which is much stronger in the public sector and embraces 33.9% of the total workforce, looks healthy indeed. In 1996, almost 1.2 million Canadian unionists (29% of the union membership in Canada) were affiliated with the AFL-CIO.