Gabriel Deville (1854-1940) was one of the theoreticians of the French Workers Party (POF) of Guesde and as such introduced Marxism into France. Deville joined the First International after the Paris Commune and was a supporter of Marx. He joined with J. Guesde to publish a number of pamphlets. He was a key leader of the French Marxist party, the Parti Ouvrier, founded in 1879, and wrote a number of documents while leading the POF, most notably an introduction to Marx's Capital. Deville moved slowly to the right during the 1880s, supporting the entry of Millerand into the bourgeois govt. He was elected to the Chamber of Deputies twice, but defeated in 1906, after which he retired from active politics.