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.
World War II by country
Nearly every country and territory in the world participated in World War II, with the exception of only a few nations which remained neutral. The Second World War pitted two alliances against each other, the Axis powers and the Allied powers. The leading Axis powers were Nazi Germany, the Kingdom of Italy and the Empire of Japan; while the United Kingdom, the United States, the Soviet Union and China were the "Big Four" Allied powers.