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.
English expedition to Portugal (1662–1668)
The war between Portugal and Spain had begun with the Portuguese revolution of 1640 and had resulted in the break up of the Iberian Union. After the peace of the Pyrenees in 1659, the independence of Portugal was threatened by a resurgent Spain, and thus Portugal asked for outside support. They turned to their old ally England but the Restoration of Charles II as monarch of England proved a concern. He had previously been allied to Spain through the Treaty of Brussels after Oliver Cromwell's Republic had been at war with Spain. Charles however immediately annulled the treaty citing King Philip IV of Spain's failure to aid in his restoration and instead answered Portugal's call for help. His marriage with Catherine of Braganza, renewed the alliance between England and Portugal despite the protestations of Spain. As part of the treaty a brigade was raised for service in Portugal in 1662 to help win her independence. The decision to send troops to Portugal came from the need to find employment for Cromwellian and Royalist veterans of the English Civil War, and the Portuguese military needed experienced veterans to help fight the Spanish.