The Portuguese Colonial War was a conflict between Portugal and its colonies (or as it likes to call them Overseas Provinces) or the War of Liberation (Guerra de Libertação), and also known as the Angolan, Guinea-Bissau and Mozambican War of Independence, was a 13-year-long conflict fought between Portugal's military and the emerging nationalist movements in Portugal's African colonies between 1961 and 1974. The Portuguese ultraconservative regime at the time, the Estado Novo, was overthrown by a military coup in 1974, and the change in government brought the conflict to an end. The war was a decisive ideological struggle in Lusophone Africa, surrounding nations, and mainland Portugal.
The prevalent Portuguese and international historical approach considers the Portuguese Colonial War as was perceived at the time - a single conflict fought in the three separate Angolan, Guinea-Bissau and Mozambican theaters of operations, rather than a number of separate conflicts as the emergent African countries aided each other and were supported by the same global powers and even the United Nations during the war. The 1954 Indian Annexation of Dadra and Nagar Haveli and 1961 Indian Annexation of Goa are sometimes included as part of the conflict.
Unlike other European nations during the 1950s and 1960s, the Portuguese Estado Novo regime did not withdraw from its African colonies, or the overseas provinces (províncias ultramarinas) as those territories had been officially called since 1951. During the 1960s, various armed independence movements became active - the People's Movement for the Liberation of Angola, National Liberation Front of Angola, National Union for the Total Independence of Angola in Angola, African Party for the Independence of Guinea and Cape Verde in Portuguese Guinea, and the Mozambique Liberation Front in Mozambique. During the ensuing conflict, atrocities were committed by all forces involved.
Throughout the period, Portugal faced increasing dissent, arms embargoes, and other punitive sanctions imposed by the international community. By 1973, the war had become increasingly unpopular due to its length and financial costs, the worsening of diplomatic relations with other United Nations members, and the role it had always played as a factor of perpetuation of the entrenched Estado Novo regime and the nondemocratic status quo in Portugal.
The end of the war came with the Carnation Revolution military coup of April 1974. The withdrawal resulted in the exodus of hundreds of thousands of Portuguese citizens plus military personnel of European, African, and mixed ethnicity from the former Portuguese territories and newly independent African nations. This migration is regarded as one of the largest peaceful migrations in the world's history although most of the migrants fled the former Portuguese territories as destitute refugees.
The former colonies faced severe problems after independence. Devastating civil wars followed in Angola and Mozambique, which lasted several decades, claimed millions of lives, and resulted in large numbers of displaced refugees. Angola and Mozambique established state-planned economies after independence, and struggled with inefficient judicial systems and bureaucracies, corruption, and poverty and unemployment. A level of social order and economic development comparable to what had existed under Portuguese rule, including during the period of the Colonial War, became the goal of the independent territories.
The former Portuguese territories in Africa became sovereign states, with Agostinho Neto in Angola, Samora Machel in Mozambique, Luís Cabral in Guinea-Bissau, Manuel Pinto da Costa in São Tomé and Príncipe, and Aristides Pereira in Cape Verde as the heads of state.