The Voluntary Militia for National Security (Italian: Milizia Volontaria per la Sicurezza Nazionale, MVSN), commonly called the Blackshirts (Italian: Camicie Nere, CCNN, singular: Camicia Nera) or squadristi (singular: squadrista), was originally the paramilitary wing of the National Fascist Party, known as the Squadrismo, and after 1923 an all-volunteer militia of the Kingdom of Italy under Fascist rule, similar to the SA.

Its members were distinguished by their black uniforms (modelled on those of the Arditi, Italy's elite troops of World War I) and their loyalty to Benito Mussolini, the Duce (leader) of Fascism, to whom they swore an oath.

The founders of the paramilitary groups were nationalist intellectuals, former army officers and young landowners opposing peasants' and country labourers' unions.

The Italian Social Republic, located in the areas of northern Italy occupied by Germany, reformed the MVSN on 8 December 1943 into the National Republican Guard (Guardia Nazionale Repubblicana, or GNR).

Benito Mussolini was the leader, or Commandant–General and First Honorary Corporal, of the Blackshirts, but executive functions were carried out by the Chief of Staff, equivalent to an army general.

The Blackshirt (Camicie Nere, or CCNN) Divisions contained regular soldiers and volunteer militia from the Fascist Party.

Mussolini also pushed through plans to raise 142 MVSN combat battalions of 650 men each to provide a Gruppo di Assalto to each army division.

The uniform jacket had black flames with two ends on the collar in place of the insignia and the lictor bundles instead of the army's stars.

[8] There was an all-black dress uniform worn by some officers and the Moschettieri del Duce ("The Leader's Musketeers", Mussolini's Guard).

[citation needed] Their ethos and sometimes their uniform were later copied by others who were influenced by Mussolini's fascism, some of which are listed below: "Blueshirts" can also refer to Canadian fascists belonging to the Canadian National Socialist Unity Party, the Chinese Blue Shirts Society and to the members of Falange Española, the most influential party within Franco's dictatorship in Spain.