A True League: Portugal and Britain

In the spring of 1373 Lisbon was faced with an attack by Henry II of Castille; and the siege was raised only by a damaging treaty of submission sworn on board a ship in the Tagus, King Ferdinand remarking resignedly: ‘How am I Henrified!’ Notwithstanding an undertaking to shun dealings with England, later in that same year he signed an agreement with Edward III, pledging friendship between the two countries.

As happened on various later occasions, Portugal found herself caught between a powerful continental neighbour, unwilling to accept the fact of her independence, and a sea-faring power bound to her by ties of trade, which at the same time regarded her as a convenient bridgehead into Europe. It was the English alliance, confirmed by the Treaty of Windsor in 1386 and often renewed, that was to prevail. In 1973, six hundred years after the first signing, Portugal is still Britain’s oldest ally.