England and Portugal have been in alliance since the year 1373, and in perpetual alliance since 1386. It is still very much in force, and the United Kingdom, as the successor polity to England, has called on Portuguese aid during the Second World War (when Portugal was neutral) and the Falklands War, using bases in the Azores for strategic purposes.

The original alliance began in 1373, ten years before the death of King Fernando I, last king of the Burgundian dynasty of Portugal. He was succeeded by civil war, and the ambitions of the king of neighbouring Castile. In the Battle of Aljubarrota on 14 August 1385 English archers asssisted the Portuguese in decisively defeating the Castilians. John of Avis, illegitimate brother of Fernando, had been regent since 1383 and proclaimed king since April 1385. Now with the English aid his reign as King João I was secure.

On 9 May 1386 the Treaty of Windsor was signed, negotiated on the English side by the protector John of Gaunt, whose daughter Philippa became João's queen the next year.

An important strengthening of the alliance happened in April 1662 when the Portuguese princess Catherine of Braganza married Charles II of England, bringing as her dowry the colonies of Bombay and Tangiers, and even more importantly the custom of drinking tea.

Another was the Peninsular War, when Napoleon, having installed his brother as puppet king of Spain, moved against Portugal. Arthur Wellesley, later the Duke of Wellington, began his campaigns, and English and Portuguese forces fought together to free the Iberian peninsula.

During the Second World War the fascist dictator Salazar would no doubt like to have followed the policy of his vile neighbour Franco, openly neutral but aiding the Nazis where possible or convenient. But the Perpetual Alliance bound him to supply the Azores as a base to the Allies.

Against all logic and cartography, these two small countries on the edge of Europe achieved vast empires from their maritime power. In recent times of course common membership of the European Union is in practice a stronger bond than this sentimental alliance, but every time we drink a glass of port we are enjoying a unique friendship.

http://www.manorhouses.com/common/portinfo.htm#Treaty%20of%20Windsor
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