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.
Causes of World War II
Between 1919 and 1939 Poland pursued a policy of balancing between the Soviet Union and Nazi Germany, seeking non-aggression treaties with both. In early 1939 Germany demanded that Poland join the Anti-Comintern Pact as a satellite state of Germany. Poland, fearing a loss of independence, refused, and Hitler told his generals on 23 May 1939 that the reason for invading Poland was not Danzig: ""Danzig is not the issue at stake. It's a matter of extending our living space in the East..."" To deter Hitler, Britain and France announced that an invasion would mean war and tried to convince the Soviet Union to join in this deterrence. The USSR however gained control of the Baltic states and parts of Poland by allying with Germany, which it did through the secret Molotov–Ribbentrop Pact in August 1939. London's attempt at deterrence failed, but Hitler did not expect a wider war. Germany invaded Poland on September 1, 1939, and rejected the British and French demands that it withdraw, resulting in their declaration of war on September 3, 1939, in accordance with the defense treaties with Poland that they had signed and publicly announced.