On December 10, 1956, in Estado Novo-ruled Portuguese Angola, the tiny undergroundAngolan Communist Party (PCA) merged with the Party of the United Struggle for Africans in Angola (PLUA) to form the People's Movement for the Liberation of Angola, with Viriato da Cruz, the President of the PCA, as Secretary General. Later other groups merged into MPLA, such as Movement for the National Independence of Angola (MINA) and theDemocratic Front for the Liberation of Angola (FDLA).
The MPLA's core base includes the Ambundu ethnic group and the educated intelligentsiaof the capital city, Luanda. The party formerly had links to European and SovietCommunist parties but is now a full-member of the Socialist International grouping of social democratic parties. The armed wing of MPLA was the Armed Forces for the Liberation of Angola (FAPLA). The FAPLA later became the national armed forces of the country.
In 1961, the MPLA joined the PAIGC, its fraternal party in Guinea-Bissau and Cabo Verde, in direct combat against the Portuguese empire in Africa. The following year, the expanded umbrella group CONCP replaced FRAIN, adding FRELIMO of Mozambique and the CLSTP, forerunner of the MLSTP of São Tomé and Príncipe.
In the early 1970s, the MPLA's guerrilla activities were more and more reduced, due to the "counter-insurgency" campaigns of the Portuguese military. At the same time, internal conflicts caused the movement to temporarily split up into three factions (Ala Presicencialista, Revolta Activa and Revolta do Leste) – a situation which was overcome in 1974/75, but which left profound scars.