Portuguese Angola Portuguese protectorate by the 1885 Treaty of Simulambuco. Sometime during the 1920s, it became incorporated into the larger colony (later the overseas province) of Portuguese Angola. The two colonies had initially been contiguous, but later became geographically separated by a narrow corridor of land, which Portugal ceded to Belgium allowing Belgian Congo access to the Atlantic Ocean. Following the decolonisation of Portuguese Angola with the 1975 Alvor Agreement, the short-lived Republic of Cabinda unilaterally declared its independence. However, Cabinda was soon overpowered and re-annexed by the newly proclaimed People's Republic of Angola and never achieved international recognition. Portuguese explorers and
Angola–Soviet Union relations United States, the People's Republic of China and the Mobutu government in Zaïre. The United States, South Africa, and several other African nations also supported Jonas Savimbi's National Union for the Total Independence of Angola (UNITA), whose ethnic and regional base lies in the Ovimbundu heartland of central Angola. The government of the Soviet Union, well aware of South African activity in southern Angola, flew Cuban soldiers into Luanda one week before November 11, 1975, the date on which Angolan nationalists had agreed to declare independence. While Cuban officers led the mission and provided the bulk of the troop force,