Portugal–United Kingdom relations

Both countries share common membership of the Atlantic Co-operation Pact, the Council of Europe, NATO, the OECD, the OSCE, the United Nations, the World Health Organization, and the World Trade Organization. Bilaterally the two countries have the Anglo-Portuguese Alliance, and a Double Taxation Convention.

History

The history of the relationship between Portugal and Britain dates back to the Middle Ages. England aided Portugal in the Reconquista, and after taking Lisbon in 1147, the first King of Portugal Afonso Henriques made the Englishman Gilbert of Hastings the Bishop of Lisbon. In 1373, the Kingdom of England signed the Anglo-Portuguese Alliance, the oldest alliance in the world still in force. The alliance was formalised by the Treaty of Windsor in 1386, and in 1387 Philippa of Lancaster, the daughter of John of Gaunt, 1st Duke of Lancaster, was married to John I of Portugal.

During the late 16th century, England found itself fighting against Spain which at this time was in personal union with Portugal. The English Armada was launched as part of this conflict in an attempt to restore Portuguese independence and counter both Spanish and Portuguese military ships which formed the Spanish Armada.

A further marriage between the Portuguese and English royal families occurred with the Marriage Treaty in 1662 when Charles II of England married Catherine of Braganza, daughter of King John IV of Portugal. Her dowry gave Britain Tangiers and Bombay, plus free trade to Portuguese colonies in Brazil and Asia. In return Charles raised a brigade of troops to serve in Portugal's Restoration War against Spain. Catherine is credited with popularising tea, which is now seen as a key part of British culture. In 1703, Portugal joined an alliance of England and the Netherlands in the War of the Spanish Succession against France and Spain. That same year, Portugal and England signed the Methuen Treaty. In the 18th century, the two nations were allies in the Seven Years' War.

The 19th century saw the alliance between Portugal and the United Kingdom come into effect once more when Napoleon Bonaparte built the Continental System, which Portugal refused to join, leading Napoleon to invade. In 1807 Napoleon's army attacked Lisbon, forcing the Portuguese royal family to flee to Brazil under the protection of the British Royal Navy. In the later half of the century, as Portugal's imperial power declined following Brazil's independence, there were disputes between itself and the United Kingdom in southern Africa (1890 British Ultimatum) which was a great embarrassment for the Portuguese monarchy and colonial prestige. Portugal was one of the Allies of World War I along with Britain. While officially neutral in World War II, Portugal remained friendly to the British, a counterpart to Spain's cooperation with the Axis.

On 13 June 2022, the Prime Minister of Portugal and the Prime Minister of the United Kingdom signed a new agreement between the two nations in London, known as the UK-Portugal Joint Declaration on Bilateral Cooperation, thereby reinforcing the Anglo-Portuguese Alliance and confirming its status as the longest-running alliance still in force. The Joint Declaration was also signed to celebrate the 650th anniversary of the Treaty of Tagilde.

The 650th anniversary of the Anglo-Portuguese Treaty of 1373 was officially commemorated by both nations on 16 June 2023. The British government stated at this time that they intend to enter into "a new bilateral Defence Agreement, due to be signed later in the year, set to take our defence cooperation to the next level."