Leon Blum, who began as a literary critic, became active in politics as a result of the Dreyfuss Affair. In 1919, he was elected to the French Chamber of Deputies. In 1925, he became the head of the Socialist Party and, in May 1936, he became France's first socialist Prime Minister since 1870. During his one year in office, he instituted a number of important social reforms, including the 40-hour work week. During World War II, he was interned by the ichy government. Following World War II, Blum served as a special ambassador to the US (1946) and the head of provisional government (1946-47). Bibliography: Bronner, Stephen Eric. Leon Blum. New York : Chelsea House Publishers, 1987. Fraser, Geoffrey. Leon Blum, Man and Statesman. Philadelphia, New York [etc.] J. B. Lippincott company [c1938] Lacouture, Jean; translated by George Holoch. Leon Blum. New York, N.Y. : Holmes & Meier, 1982. Logue, William. Leon Blum, the Formative Years– 1872-1914. 1973. Northern Illinois University Press.