King João I (1357 - 1433)
The tenth King of Portugal, João was born on 11 April 1357. He was the illegitimate son of Pedro I and Teresa Lourenço, the young daughter of the Lisbon merchant, Lourenço Martins.
After the death of King Fernando I [who left no male heir to the throne,] Portugal entered into a period of great instability and wars of succession with Castile.
Politically astute, João had the backing of two men who were essential to his cause: João das Regras and Nuno Álvares Pereira. Thanks to the intellect of the man of law (Regras) and the strategic nous and dedication of the Constable of the Realm (Álvares Pereira), João, who had meanwhile been made a Master of the Order of Aviz, assumed leadership of the realm and was proclaimed King João I, thus establishing the Aviz dynasty.
He married the daughter of the Duke of Lancaster, Philippa and, from 1387 onwards, they produced what came to be known as the Illustrious Generation: the princes Duarte, Fernando, Henrique (Henry the Navigator) and Pedro.
Of these, the figure and achievements of Henry the Navigator are probably the most well known to world history. He was the strategist behind the period of expansion brought about by the Portuguese Discoveries.
Thanks to João's influence, Henry the Navigator was appointed Governor of the Order of Christ, initiating a close connection between the military and religious order and the Portuguese crown.
João I died in 1433. He is buried, with his family, in the Monastery of Santa Maria da Vitória in Batalha, a mythical place in Portuguese history, the monastery having been erected to celebrate the Portuguese victory in the Battle of Aljubarrota in 1385.