Treaty of Windsor 1386 - Historic UK

On May 9, 1386, the Treaty of Windsor between Portugal and England took place. It is the oldest diplomatic alliance in the world still in force. A short excerpt:

"On 9th May 1386 the diplomatic alliance between Portugal and England was ratified by the Treaty of Windsor. The oldest peace treaty in Europe was finalised through the marriage of King John I of Portugal to Philippa of Lancaster. The guarantee of support and mutual understanding between the countries survived centuries of upheaval, conflict on the Iberian Peninsula and the engagement of both parties in numerous wars. The historic relationship was cemented back in 1386 and perseveres to this day.

The foundations of this special alliance can be traced back to the Middle Ages. The English had initially intervened and offered support to the Portuguese Crown back in 1147 with the Siege of Lisbon. The King at the time, Afonso Henriques was offered support from the English in order to conquer Lisbon and take the city from the Moors, which he eventually achieved with a little help from his northern counterparts. The English soldiers had been on their way to the Holy Land in order to wage war as part of the Second Crusades. In giving their assistance, the English and Portuguese first began to see each other as friendly European neighbours who could come to support one another in times of need.

The initial foundations of the alliance subsequently came together in 1373 when an Anglo-Portuguese Treaty was agreed between King Edward III and King Ferdinand and Queen Eleanor of Portugal. The agreement established a friendship and international union that would be bolstered by the Treaty of Windsor and reinforced throughout the following centuries in the interests of the two nations."