Claes Emil Tholin (22 October 1860 in the former Södra Säm parish near Gällstad, Älvsborgs län – 27 June 1927 in Stockholm) was the first leader of the Swedish Social Democratic Party 1896–1907, after collective leadership had been applied in 1889–1896. He was a tailor by occupation. In the years 1880–1890 he worked in Copenhagen and became a member of the tailor's union board there. After returning to Sweden he continued his work as a tailor while becoming a leading force in the Swedish social democratic movement.^[1]

In 1907, he was hired by the Swedish Trade Union Confederation (the "LO" - Landsorganisationen i Sverige) as their organizing ombudsman, coordinating organization efforts and speaking at rallies. He continued this work until 1919, when he became a member of Work Council tasked by the government with implementing the eight hour day.^[2]