Popular Unity was a short-lived social-democratic

Social democracy

Social democracy is a political ideology of the center-left on the political spectrum. Social democracy is officially a form of evolutionary reformist socialism. It supports class collaboration as the course to achieve socialism...

 and social-liberal

Social liberalism

Social liberalism is the belief that liberalism should include social justice. It differs from classical liberalism in that it believes the legitimate role of the state includes addressing economic and social issues such as unemployment, health care, and education while simultaneously expanding...

 political party in Italy.

It was formed in April 1953 by disgruntled members of the Italian Democratic Socialist Party

Italian Democratic Socialist Party

The Italian Democratic Socialist Party is a minor social-democratic political party in Italy. Mimmo Magistro is the party leader. The PSDI, before the 1990s decline in votes and members, had been an important force in Italian politics, being the longest serving partner in government for Christian...

 (PSDI) and the Italian Republican Party

Italian Republican Party

The Italian Republican Party is a liberal political party in Italy.The PRI is party with old roots that originally took a left-wing position, claiming descent from the political position of Giuseppe Mazzini...

 (PRI), who did not agree with the new electoral law approved by the Parliament with the support of their parties. Its leaders were Piero Calamandrei

Piero Calamandrei

Piero Calamandrei was an Italian author, jurist, soldier, university professor and politician. He was one of Italy's leading authorities on the law of civil procedure....

, a Democratic Socialist, and Ferruccio Parri

Ferruccio Parri

Ferruccio Parri was an Italian partisan and politician who served as the 43rd Prime Minister of Italy for several months in 1945. During the resistance he was known as Maurizio.-Biography:...

, a Republican former Prime Minister. The party won 0.6% of the vote in the 1953 general election

Italian general election, 1953

The Italian elections of 1953 were held on June 7. They were a test for leading centrist coalition ruled by Prime Minister Alcide De Gasperi. Italian electors chose the second Parliament of the Italian Republic.-The Scam Law:...

.

The party was active until 1957. After that, some of its members, including Parri, joined the Italian Socialist Party

Italian Socialist Party

The Italian Socialist Party was a socialist and later social-democratic political party in Italy founded in Genoa in 1892.Once the dominant leftist party in Italy, it was eclipsed in status by the Italian Communist Party following World War II...

, but most of them returned to their former parties.