William Z. Foster (1881-1961), born in Taunton, Mass., was a member of the Socialist Party of America from 1901 to 1909, joined the United Wage Workers' Party of Washington in 1909, and became a member of the IWW
in 1910, participating in the Spokane free-speech campaign.
He then traveled to Europe, where he became a convert to the strategy of "boring from within" existing trade unions.
After unsuccessfully contesting the AFL's right to represent the American labor movement at the 1911 meeting of the International Secretariat in Budapest, Foster returned to the United States and settled in Chicago. He left the IWW in 1912, joined the Brotherhood of Railway Carmen of America, and subsequently organized the Syndicalist League of North America and the International Trade Union Educational League.