Arturo Labriola (Italian: [labriˈoːla]; 21 January 1873 – 23 June 1959) was an Italian revolutionary syndicalist and socialist politician and journalist.
Labriola was born in Naples on 21 January 1873 to Luigi Labriola, an artisan. While studying jurisprudence in University of Naples, Arturo Labriola started his political activity. In 1891 he joined the Republican-Socialist University Circle. Between 1892-1895, he collaborated on various periodicals: Socialismo Popolare, edited by Carlo Monicelli, Rivista Popolare di Politica, Litteratura e Scienze Sociali, edited by Napoleone Colajanni and Critica Sociale, edited by Filippo Turati. In 1894-1895, Labriola was involved with the Fasci Siciliani and therefore was suspended for one year from university studies. In 1897, Labriola joined Italian Socialist Party (PSI) and fought in the Greco-Turkish War in Crete.
In May 1898, workers in Milan organized strikes and protests to demonstrate against the government. The riots were brutally repressed: troops fired on demonstrators, and Filippo Turati was arrested, accused of inspiring the riots. Labriola fled to Geneva in order to elude arrest. There, he taught at University of Geneva and worked with Vilfredo Pareto. Labriola was expelled from Switzerland in the same year and moved to Paris. In Paris he met the socialists Georges Sorel, Hubert Lagardelle and Paul Lafargue.