Italian Socialist Party of Proletarian Unity

The Italian Socialist Party of Proletarian Unity (Partito Socialista Italiano di Unità Proletaria, PSIUP), was a political party in Italy from 1964 to 1972.

Italian Socialist Party of Proletarian Unity

Partito Socialista Italiano di Unità Proletaria
PresidentLelio Basso
General SecretaryTullio Vecchietti
SpokespersonDario Valori
Founded12 January 1964 (1964-01-12)
Dissolved13 July 1972 (1972-07-13)
Split fromItalian Socialist Party
Merged intoItalian Communist Party
HeadquartersRome, Italy
NewspaperMondo nuovo
Political positionLeft-wing to far-left
Colours     Red


The PSIUP was formed on 12 January 1964 by a leftist section of the Italian Socialist Party (PSI). PSIUP had been the PSI's name in 1943-1947. The new PSIUP was led by Tullio Vecchietti. Other leading members were Lelio Basso, Vittorio Foa, Lucio Libertini, Emilio Lussu, Francesco Cacciatore detto Cecchino and Dario Valori.

The new party attracted PSI militants who were dissatisfied with the close cooperation between the PSI and the Christian Democracy. Instead the founders of the PSIUP favoured cooperation with the Italian Communist Party (PCI).

On 13 July 1972, following a disappointing electoral result, the PSIUP split. The majority, led by Libertini, Valori and Vecchietti, joined the PCI. The rightist minority, led by Giuseppe Avolio, Nicola Corretto and Vincenzo Gatto, rejoined the PSI. The leftist minority, led by Foa and Silvano Miniati, continued to work under the name PSIUP, and in December 1972 they established the Proletarian Unity Party (PdUP).

A Posadist faction within the PSIUP published the Bollettino della sinistra rivoluzionaria del PSIUP between 1965 and 1967.

Electoral resultsEdit

Italian ParliamentEdit

Chamber of Deputies
Election year Votes % Seats +/− Leader
1968 1,414,697 (5th) 4.5
23 / 630
Lelio Basso
1972 648,591 (8th) 1.9
0 / 630
Lelio Basso
Senate of the Republic
Election year Votes % Seats +/− Leader
1968 into PCI
13 / 315
Lelio Basso
1972 into PCI
11 / 315
Lelio Basso


  • Tullio Vecchietti (January 1964 - September 1971)
  • Dario Valori (October 1971 - July 1972)

See alsoEdit

  • Giuseppe Impastato, anti-mafia journalist member of the party, assassinated on May 9, 1978

External linksEdit