The Arditi del Popolo (The People's Daring Ones) was an Italian militant anti-fascist group founded at the end of June 1921 to resist the rise of Benito Mussolini's National Fascist Party and the violence of the Blackshirts (squadristi) paramilitaries. It grouped revolutionary trade-unionists, socialists, communists, anarchists, republicans, etc., as well as some former military officers, and was co-founded by Mingrino, Argo Secondari, Gino Lucetti – who tried to assassinate Mussolini on 11 September 1926 – the deputy Guido Picelli and others. The Arditi del Popolo were an offshoot of the Arditi elite troops, who had previously occupied Fiume in 1919 behind the poet Gabriele d'Annunzio, who proclaimed the Italian Regency of Carnaro. Those who split to form the Arditi del Popolo were close to the anarchist Argo Secondari and were supported by Mario Carli. The formazioni di difesa proletaria (Proletarian Defense Formations) later merged with them. The Arditi gathered approximately 20,000 members in summer 1921.
Composed of socialists, anarchists and communists, the Arditi del Popolo was not supported by the socialist parties (neither by the Italian Socialist Party, PSI, nor by the Communist Party of Italy, PCI). The Arditi were criticized by the socialist newspaper Avanti! on July 7, 1921, following a demonstration in Rome the previous day.