Polish Socialist Party-Left Wing

(PSP-LEFT WING, Polska Partia Socjalistyczna-Lewica), a workers’ party in the Kingdom of Poland from 1906 to 1918.

The PSP-Left Wing was formed at the Ninth Congress of the Polish Socialist Party, held in November 1906, as the result of a break between the party majority (led by M. Bielecki, H. Walecki, W. Kostrzewa, and F. Kon) and Piłlsudski’s followers. It gradually became a Marxist organization. Between 1908 and 1910 the party functioned for the most part through legal trade unions, cultural and educational institutions, and other organizations. At the outbreak of World War I it took an internationalist position. The party sent delegates to the Zimmerwald Conference in 1915 and to the Kienthal Conference in 1916, and it welcomed the Great October Socialist Revolution. The party’s merger with the Social Democracy of the Kingdom of Poland and Lithuania on Dec. 16, 1918, laid the foundation for the Communist Party of Poland.