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Important Figures

King John I

The tenth king of Portugal (1385-1433) and the first king of the second dynasty, also known as the Avis dynasty.

He was the illegitimate son of King Pedro and Teresa Lourenço but was raised at court and had an excellent education. In 1364, at just 7 years old, he was consecrated Master of the Order of Avis.

With the death of his brother, King Ferdinand, and after internal revolts and military clashes with Castile, supporters of the independence cause rallied around the Master of Avis.

Although Lisbon was one of the cities most supportive of John I, the castle continued to be guarded by a supporter of Dona Leonor and the Castilian cause. It was therefore surrounded and attacked by supporters of King John until it surrendered.

John I was crowned king in April 1385 and on 14 August of the same year he confronted the King of Castile with a small army made up of Portuguese and English soldiers. They faced a Castilian army that was superior both in men and arms at what would become known as the most emblematic battle to take place on Portuguese territory: the Battle of Aljubarrota.

This battle helped to strengthen the cause and consolidate the monarch as king.

It was during his reign (the longest of the Portuguese monarchy) that the conquests in North Africa began, laying the foundations for the maritime expansion that would be gain pace in subsequent reigns.

He was known for being a just ruler, erudite, devout and an expert warrior.

He also undertook extensive building works at the castle.

Did you know that…

There were Portuguese fighting on both sides at the Battle of Aljubarrota? Some were fighting for the Castilian cause, which supported Beatrice, daughter of King Ferdinand, who was married to the King of Spain. Others were backing the Master of Avis, who was fighting for the independence of the kingdom.