He was born Louis Boudianoff (Leib Budiansky) in Korsun-Shevchenkivskyi, Cherkassy Oblast, Ukraine, then under the rule of imperial Russia on February 15, 1874. He was born into a middle-class Jewish family, the son of a shirt manufacturer.
At first, Boudin was a member of the Socialist Labor Party of America. He was also a member of the governing National Executive Board of the party's trade union affiliate, the Socialist Trade and Labor Alliance from 1898 to 1899.
Boudin left the Socialist Labor Party during the party fight of 1899, casting his lot with the dissident faction headed by Morris Hillquit and Henry Slobodin. This dissident organization eventually became one of the main pillars of the new Socialist Party of America, established in the summer of 1901.
Boudin was elected a delegate of the Socialist Party of America to the International Socialist Congress in Stuttgart in 1907 and the 1910 Copenhagen Congress of the Second International.
Boudin was frequently a candidate for public office on the Socialist Party ticket. He ran for Judge of the New York Court of Appeals in 1910, 1914 and 1917, and for Chief Judge in 1916. He also ran for Justice of the New York Supreme Court (2nd District) in 1910, 1912, and 1919.
After the formation of the Communist Labor Party of America and the Communist Party of America, Boudin shied away from organized politics but taught in the Communist Party-sponsored Workers' School in New York in the late 1920s and occasionally contributed articles to the CP's artistic magazine, The New Masses, in the second half of the 1930s.
Louis was the great uncle of domestic terrorist bomber and murderer Kathy Boudin, who is the mother of San Francisco's District Attorney.
