Language federations were formed in the late 19th and early 20th century by immigrants to the United States, primarily from Eastern and Southern Europe, who shared a commitment to some form of socialist politics. Some of these groups joined the Socialist Labor Party of America (SLP); later, many joined the Socialist Party of America (SPA) and then later joined one of the precursors of the Communist Party USA (CPUSA); a number of federations also remained in the Socialist Party. The Russian and Finnish federations were particularly important in the early years of the Communist Party. Historical overview The Language Federations also served as an important cultural resource for immigrants, allowing them to maintain contact with political developments in their homelands and providing a gathering place for strangers in a strange land. Many groups had their own halls for dances and social gatherings which still exist, in name if not in function, in America's largest cities of the East and West Coasts and Midwest. Each Language Federation arose at different times, as members of those national, ethnic or religious groups arrived in the United States. In addition, they typically sprung up at the grassroots level, affiliating with other local groups to form national federations before attaching themselves to political parties. They often resisted attempts by the parties to which they were affiliated to bring them into line with the aims or platform of the group as a whole; indeed, at some points the various Language Federations made up such a large portion of socialist groups as to make top-down dictation of a uniform policy very difficult. The SPA had a vexed relation with language federations: while it began recognizing them in the first decade of the 20th century and incorporating them within the party in the decade that followed, the party had often veered in the direction of nativism, particularly in the case of exclusion of Asian workers, but also directed against Eastern and Southern European immigrants. The SPA often appeared as if it did not know what to make of these foreign-language organizations and let them develop more or less independently. Even so, they grew exponentially during World War I and made up roughly half the SPA by 1918. The SPA's executive committee formally expelled seven of these language federations in May 1919 when it became clear that they favored the left wing in the impending split within the party.