Portugal during World War II
Upon the start of World War II in 1939, the Portuguese Government announced on 1 September that the 600-year-old Anglo-Portuguese Alliance remained intact, but that since the British did not seek Portuguese assistance, Portugal was free to remain neutral in the war and would do so. In an aide-mémoire of 5 September 1939, the British Government confirmed the understanding. As Hitler's occupation swept across Europe, neutral Portugal became one of the Continent's last escape routes. Portugal managed to remain neutral throughout the war despite extraordinary pressures from both sides, notably over the strategically located Azores islands and over the wolfram (tungsten) trade.
Rhodesian mission in Lisbon
British policy-makers regarded Portugal as a traditional friend—the Anglo-Portuguese Alliance dated back to 1386, and both countries were in the North Atlantic Treaty Organisation (NATO) and the European Free Trade Association—but the combined strength of the communist bloc and the Afro-Asian lobby in the United Nations forced the British to peel back their support for the pluricontinental "Estado Novo" ("New State") during the early 1960s. Portugal's Colonial War, starting in Angola in 1961, pitted it against a number of guerrilla factions in its African territories, most of which subscribed to communist political thinking. Britain opposed communist encroachment into southern Africa, but knew it would become an international pariah if it publicly opposed general consensus at the UN, which roundly condemned colonialism in all forms and supported communist-backed insurgencies across the region, regarding them as racial liberation movements. It therefore attempted an awkward balancing act whereby it would appear to oppose Portugal without meaningfully doing so.