The Unique Friendship Between Portugal and the UK

When people think of historic alliances, they might picture the complex entanglements of European monarchies or the strategic partnerships of modern geopolitical powers. But one of the oldest, most enduring international relationships in history is the Anglo-Portuguese Alliance—a bond between Portugal and the United Kingdom that stretches back over six centuries. Despite their differences in size, power, and geography, these two nations have shared a fascinating and resilient relationship that has survived wars, revolutions, and changing world orders.

This isn’t just any alliance—it's the oldest still-in-force diplomatic alliance in the world, dating back to 1386. Yet beyond treaties and pacts, the ties between Portugal and the UK have been woven into history, culture, and even shared battles. Let’s dive into the unique story of how Portugal and the UK forged an unshakable bond and why their relationship remains significant to this day.

The Beginning: The Treaty of Windsor (1386)

The foundation of the Anglo-Portuguese alliance was laid in a world that looked very different from today. It was the Middle Ages, and European powers were locked in battles for territory, influence, and prestige. In this context, Portugal and England (as the UK was known before unification with Scotland in 1707) signed the Treaty of Windsor in 1386.

The treaty was a formal agreement between King John I of Portugal and King Richard II of England, following Portugal's victory in the Battle of Aljubarrota, where English archers had supported the Portuguese in securing their independence from Castile. The Treaty of Windsor established a pact of “perpetual friendship” between the two nations, ensuring mutual support and non-aggression.

Unlike many treaties of the time, which often dissolved amid changing political landscapes, the Treaty of Windsor created a bond that stood the test of time. It symbolized not just military cooperation but a deeper sense of trust and partnership. The marriage of Philippa of Lancaster, the daughter of England’s John of Gaunt, to King John I of Portugal shortly after the treaty further cemented the alliance, blending royal bloodlines and creating dynastic ties between the two countries.

The Age of Exploration: Mutual Benefits and Maritime Collaboration

In the centuries that followed, Portugal and the UK both emerged as significant maritime powers, but their alliance persisted even as they pursued separate paths to global dominance. The Age of Exploration in the 15th and 16th centuries was a pivotal era for Portugal, whose explorers—like Vasco da Gama and Pedro Álvares Cabral—pioneered sea routes to India, Africa, and Brazil, laying the groundwork for the Portuguese Empire.

During this time, England was still a developing naval power, and it observed Portugal’s success with interest. The two nations, united by the sea and their ambitions for global trade, continued to support one another. While Portugal secured its routes to the Spice Islands and Brazil, England would later rely on Portugal’s experience and knowledge in the maritime world.

Their mutual respect for naval prowess would come in handy during later conflicts, as both countries realized that they could benefit from their shared interests in maintaining dominance at sea. In many ways, the Anglo-Portuguese alliance laid the groundwork for the maritime cooperation that would define both nations' roles on the world stage for centuries to come.

The Napoleonic Wars: A Renewed Partnership

While Portugal and the UK’s bond may have been born in the medieval period, it was tested and reaffirmed during the Napoleonic Wars in the early 19th century. At this time, Europe was in turmoil, with Napoleon’s French Empire seeking to dominate the continent. Portugal, caught between its ally Britain and an aggressive France, faced an existential crisis when Napoleon demanded Portugal sever ties with the UK.

Rather than betray its centuries-old ally, Portugal stood firm, choosing to honor its relationship with Britain. This decision had dramatic consequences—Napoleon’s forces invaded Portugal, and the Portuguese royal family was forced to flee to Brazil, then part of the Portuguese empire. Britain, in turn, sent troops to Portugal, beginning what is known as the Peninsular War (1807-1814).

One of the key figures during this war was Arthur Wellesley, better known as the Duke of Wellington. His successful campaign, in collaboration with Portuguese forces, pushed the French out of the Iberian Peninsula and restored Portuguese sovereignty. This military cooperation became one of the most important moments in the Anglo-Portuguese relationship, renewing the alliance and proving that even under intense pressure, the two nations would stand by each other.

Wine, Trade, and Cultural Exchange

Beyond wars and treaties, one of the most enduring aspects of the relationship between Portugal and the UK has been their cultural and economic exchange, particularly around wine. The British have long had a love affair with Portuguese wine, especially port, which became a staple in Britain thanks to the Methuen Treaty of 1703. This treaty allowed Portuguese wine to be imported into England at lower duties, creating a booming market for port wine in British society that continues to this day.

The British-Portuguese connection is deeply ingrained in the Douro Valley, Portugal’s famous wine region. Many of the region's most prominent port wine houses—such as Taylor's, Graham's, and Warre's—were founded by British families in the 18th century, and some are still family-run today. The wine trade helped cement economic ties between the two nations, and British influence can still be felt in Portugal’s wine culture.

Over time, these economic relationships blossomed into deeper cultural exchanges. Many English families settled in Portugal, particularly in cities like Lisbon and Porto, contributing to the cosmopolitan feel of these places. The British presence in Portugal became so significant that a neighborhood in Lisbon is still known as the "British Cemetery", home to English residents from the 18th century onwards.

World War II: Portugal’s Neutrality, Britain’s Trust

One of the most interesting moments in the Anglo-Portuguese alliance came during World War II, when Portugal, under the dictatorship of António de Oliveira Salazar, remained officially neutral. However, despite this neutrality, Portugal’s strategic location in the Atlantic Ocean made it crucial to the Allied war effort.

The British, aware of their centuries-old alliance, trusted Portugal to act in their interests while maintaining neutrality. Salazar allowed the Allies to use the Azores, a Portuguese archipelago in the Atlantic, as a key base for naval and air operations. The Azores played a vital role in controlling the Atlantic shipping lanes, contributing to the eventual Allied victory.

Portugal’s delicate balancing act during World War II is a testament to the deep trust that had developed between the two nations over centuries. Despite the formal stance of neutrality, Portugal found ways to aid its old ally, keeping the spirit of the Treaty of Windsor alive even in the most challenging times.

A Modern Relationship: A Lasting Legacy

In the modern era, the relationship between Portugal and the UK has evolved into one of mutual respect and cooperation within the context of the European Union, NATO, and international diplomacy. Even after the UK’s decision to leave the EU, the bond between the two countries remains strong, particularly in areas like trade, tourism, and defense.

Portugal remains one of the UK's closest allies in southern Europe, and the deep cultural ties fostered over the centuries continue to thrive. Thousands of British expatriates live in Portugal, particularly in the Algarve, and British tourists are among the most frequent visitors to Portugal’s sunny beaches and historic cities. At the same time, Portuguese communities in the UK have flourished, bringing the flavors, sounds, and traditions of Portugal to cities like London.

Conclusion: A Relationship Rooted in History, Flourishing in the Present

The relationship between Portugal and the UK is one of the most fascinating examples of enduring diplomacy in world history. What began as a medieval alliance of convenience has grown into a partnership marked by trust, mutual respect, and a shared love of culture. From military campaigns to wine production, from wartime diplomacy to modern trade, the connection between these two nations runs deep.

As the world continues to change, one thing is clear: the Anglo-Portuguese alliance has stood the test of time and will continue to influence the destinies of both nations for generations to come.