Although Marxist influences were evident before independence, Marxism-Leninism had not been the MPLA's stated ideology. But during a plenum of the MPLA Central Committee in October 1976, the party formally adopted Marxism-Leninism. The plenum also resulted in several major organizational decisions, including the creation of a secretariat, a commission to direct and control the Department of Political Orientation, and the Department of Information and Propaganda. The National Party School, founded in February 1977, trained party cadres to fill national and provincial party positions, and at the First Party Congress in December 1977, the MPLA transformed itself into a vanguard Marxist-Leninist party to be called the Popular Movement for the Liberation of AngolaWorkers ' Party (Movimento Popular de Libertação de Angola-Partido de Trabalho--MPLA-PT).

The estimated 110,000 members of the MPLA-PT had widely diverse backgrounds and political ideas, which made factionalism inevitable. The Neto regime soon faced problems generated by independent left-wing organizations and militant workers. Neto made the first public reference to internal dissent on February 6, 1976, when he denounced a demonstration that had protested the termination of a popular radio program that had been critical of the new government and that had demanded rule by workers and peasants. The government arrested some of the demonstrators and launched a major crackdown on opposition elements. One of these was the so-called Active Revolt, a faction founded in 1973 that comprised intellectuals of varying political orientation andincluded the MPLA's first president, Mário de Andrade, and other prominent MPLA leaders. Another opposition element was the Organization of Angolan Communists (Organização dos Comunistas de Angola -- OCA), a Maoist movement founded in 1975 that attacked the MPLA as a bourgeois party, condemned Soviet imperialism, and called for the withdrawal of all Cuban forces.

Data as of February 1989