The oldest diplomatic alliance in the world celebrated with joint military parade

British Army soldiers paraded with their Portuguese counterparts at Buckingham Palace to commemorate the 650th Anniversary of the Anglo-Portuguese Alliance, the oldest diplomatic alliance in the world still in force.

UK Foreign Secretary James Cleverly said of the six-and-a-half-century-long partnership: “No other relationship on the planet has survived the test of time as well as ours. We are now building on those solid foundations to deliver security and prosperity for our countries, progress towards net zero, and support to Ukraine.”

No other relationship on the planet has survived the test of time as well as ours

JAMES CLEVERLY, UK FOREIGN SECRETARY

In a tangible sign of that partnership, a combined Guard of Honour of UK and Portuguese military paraded side by side in Buckingham Palace Quadrangle to receive His Majesty King Charles III and His Excellency The President of Portugal.

Nijmegen Company Grenadier Guards made up the UK component of the Guard of Honour and musical support was given by the Band of the Welsh Guards, who played the British National Anthem as His Majesty The King Charles III arrived on the dais.

As the visiting President of Portugal exited his car and joined His Majesty on the dais, he was greeted with “Royal Salute, Present Arms”, the Colours (ceremonial flags) were lowered, and the Band of the Welsh Guards played the Portuguese National Anthem.

In a further symbol of equal partnership, the Captains of both the UK & the Portuguese contingents moved to the dais together and saluted. The Captain of the Portuguese contingent invited The King to inspect his Portuguese armed forces, and the Captain of the Grenadier Guards speaking in perfect Portuguese (as is the respectful custom to use the native language of a visiting head of state), invited the Portuguese President to inspect the UK troops.

After the inspection, both leaders moved to Marlborough Road to be received by a tri-service step lining party, a tri-service contingent of Portuguese military personnel, and mounted and dismounted troops of the British Army’s Household Cavalry Mounted Regiment on parade with their Sovereign’s Standard.

The King and The President then attended a Commemoration Service in The Queen’s Chapel with music performed by the RAF String Quartet. The State Trumpeters of the Band of the Household Cavalry, dressed in their gold state coats emblazoned with The King’s cypher, announced the VIPs’ arrival on silver trumpets.

The alliance is a pact of perpetual friendship between the two countries.

Historically, the Kingdom of Portugal and the Kingdom of England, and later the modern Portuguese Republic and United Kingdom, have never waged war against each other nor have they participated in wars on opposite sides as independent states since the signing of the Treaty of Windsor.

The alliance has served both countries throughout their respective military histories, influencing the participation of the United Kingdom in the Peninsular War, the UK's major land contribution to the Napoleonic Wars and the establishment of an Anglo-American base in Portugal. Portugal aided England (and later the UK) in times of need, for example, in the First World War.

Portugal and the United Kingdom were two of the founding members of NATO, in 1949. Today both nations are providing practical aid and support to Ukraine and will sign a new bilateral Defence Agreement later this year.

The alliance has had huge benefits for trade too. King Edward III’s granddaughter (and John of Gaunt’s daughter), Philippa of Lancaster, married King John I of Portugal in February 1387 producing the "Illustrious Generation", which led Portugal into its golden age, during the period of the Voyages of Discoveries. Philippa provided royal patronage for English commercial interests that sought to meet the Portuguese desire for cod and cloth in return for wine, cork, salt, and oil shipped through the English warehouses at Porto.

Later Tangier and Bombay were ceded to Britain as part of Catherine of Braganza’s Dowry when she married King Charles II in the 17th century. During the Napoleonic wars 1803-1815, Portugal was the only country in Europe to challenge Napoleon’s blockade of British trade. Trade between the UK and Portugal is worth £11.6 billion today.

The beginning of the formalisation of this ancient Alliance, based on a perpetual friendship between the two countries, occurred with the signing of the Treaty of Tagilde in 1372 by John of Gaunt and the Portuguese King. The Alliance was formally constituted by the Treaty of Peace, Friendship and Alliance, and sealed at St. Paul’s Cathedral, London, on 16 June 1373 by King Edward III of England and King Ferdinand & Queen Eleanor of Portugal. This alliance was renewed in the Treaty of Windsor of 1386 and in several other treaties throughout the centuries.

The most important part of the original treaty stated that:

It is cordially agreed that if, in time to come, one of the kings or his heir shall need the support of the other, or his help, and in order to get such assistance applies to his ally in lawful manner, the ally shall be bound to give aid and succour to the other, so far as he is able (without any deceit, fraud, or pretence) to the extent required by the danger to his ally’s realms, lands, domains, and subjects; and he shall be firmly bound by these present alliances to do this.