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.
20th-century events
Soon after the events in Czechoslovakia, Britain and France issued assurances of protection to Poland, which seemed to be next on Hitler's list. World War II officially began on September 1, 1939, when Hitler unleashed his Blitzkrieg, or lightning war, against Poland. Britain and France, much to Hitler's surprise, immediately declared war upon Germany, but the help they delivered to Poland was negligible. Sixteen days later, Poland was attacked from the East by Soviet Union, acting in a secret alliance with Nazi Germany. After only a few weeks, the Polish forces were overwhelmed, and its government fled to exile in London (see Polish government in Exile).