United Left was an alliance of leftist political parties

Political Parties

Political Parties: A Sociological Study of the Oligarchical Tendencies of Modern Democracy is a book by sociologist Robert Michels, published in 1911 , and first introducing the concept of iron law of oligarchy...

 in Peru

Peru

Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....

 founded in 1980 by Popular Democratic Unity

Popular Democratic Unity

Popular Democratic Unity , was a political front in Peru founded in 1977 by Revolutionary Vanguard, Revolutionary Communist Party and Revolutionary Left Movement. UDP contested the 1978 and 1980 elections....

 (UDP), Revolutionary Left Union

Revolutionary Left Union

Revolutionary Left Union , was an electoral front in Peru founded in 1980 by Communist Party of Peru , Revolutionary Vanguard and National Liberation Front. UNIR participated on the lists of IU from the municipal elections 1980 to 1993....

 (UNIR), Peruvian Communist Party

Peruvian Communist Party

The Peruvian Communist Party is a communist party in Peru. It was founded in 1928 by José Carlos Mariátegui, under the name Partido Socialista del Perú . In 1930 the name was changed to PCP...

 (PCP), Revolutionary Socialist Party

Revolutionary Socialist Party (Peru)

Revolutionary Socialist Party , a political party in Peru formed in November 1976 by a group of radical army officers who had been active in the "first phase of the revolution" under Velasco Alvarado and who subsequently advocated a return to the objectives of the 1968 coup.Its founders included...

 (PSR), Revolutionary Communist Party

Revolutionary Communist Party (Peru)

Revolutionary Communist Party was a communist party in Peru. PCR was formed in 1974, through a split in the Revolutionary Vanguard. PCR was founded by Manuel Danmert, Agustín Haya and Santiago Pedraglio....

 (PCR) and FOCEP.

In 1984 UDP and a part of PCR converted itself into the Mariateguist Unified Party

Mariateguist Unified Party

Mariateguist Unified Party was a political party in Peru founded in 1984 by Revolutionary Vanguard , Revolutionary Left Movement , Workers Revolutionary Party and a sector of Revolutionary Communist Party...

 (PUM). PUM integrated itself in IU.

IU was led by Alfonso Barrantes Lingán

Alfonso Barrantes Lingán

Alfonso Barrantes Lingán was a Peruvian politician most active in the mid-1980s.-Mayor of Lima:Affiliated with the United Left Party, he was the mayor of Lima from 1984 to 1986...

 (who lost to Alan García in the 1985 elections) up to 1987. In 1989 IU held its first congress. Gradually the IU disintegrated, with more and more groups deserting it.