Communist Party of Cuba

Cuba had communist and socialist organisations from the early years of the republic. According to the Spanish-language source, the first Communist Party of Cuba was founded in 1925 by Julio Antonio Mella, Carlos Baliño and others, with José Miguel Pérez as its first secretary-general. It was illegal until 1938, took the name Revolutionary Communist Union in 1939 and Popular Socialist Party (PSP) in 1944. The PSP backed Fulgencio Batista's presidential candidacy for 1940–1944, and Juan Marinello and Carlos Rafael Rodríguez served in his cabinet, but it was outlawed under Batista's dictatorship in 1953. That year the PSP condemned the attack on the Moncada barracks by Fidel Castro and his followers, and until December 1958 its attitude towards the 26th of July Movement was ambiguous.

In July 1961 Castro's 26th of July Movement, the PSP led by Blas Roca and part of the student-based Revolutionary Directory led by Faure Chomón merged into the Integrated Revolutionary Organizations (ORI). After a purge of the "errors of sectarianism" committed by some of its leaders, the ORI became the United Party of the Cuban Socialist Revolution (PURSC) on 26 March 1962 and the Communist Party of Cuba on 3 October 1965. The next day the first issue of Granma, the organ of the Central Committee, appeared. According to the Spanish-language source, Aníbal Escalante and more than 40 others were imprisoned in the "microfaction" affair of 1966–1968.

According to the English-language source, for its first fifteen years the party was almost completely inactive outside the Politburo. Its 100-member Central Committee rarely met, and in 1969 its 55,000 members, 0.7% of the population, made it the smallest ruling communist party in the world. By the First Congress in 1975 it had just over 200,000 members, rising to over 430,000 by 1980 and 520,000 by 1985. Article 5 of the 1976 constitution recognised the party as "the superior guiding force of society and of the State". The Secretariat was merged into an expanded Politburo in 1991 and later re-established, in 2002 according to the English-language source and in 2006 according to the Spanish-language source.

Fidel Castro was First Secretary from the party's foundation, with Raúl Castro as Second Secretary. The sources differ on when Raúl took over: the English-language source links it to Fidel's resignation in 2008, while the Spanish-language source says Fidel's tenure as First Secretary ended at the Sixth Congress in April 2011. The Sixth Congress approved guidelines for economic and social policy, and Raúl's government expanded worker cooperatives and small private businesses. The constitution approved by referendum in 2019 recognised private property and foreign direct investment. At the Eighth Congress on 16–19 April 2021 Miguel Díaz-Canel was elected First Secretary. The English-language source states that the party governs Cuba as an authoritarian one-party state in which dissent and political opposition are prohibited and repressed. Abroad, the party supported left-wing revolutionary movements such as the Sandinistas in Nicaragua and the New Jewel Movement in Grenada, and intervened in the Angolan civil war.