The battle became a turning point in Portuguese and world history, and King John I and his military aide, Constable Nuno Álvares Pereira, became immortal idols.

King John I had a first illegitimate son, Afonso, and a daughter Beatrice; after marrying Philippa of Lancaster, John of Gaunt's daughter, and establishing the House of Aviz, they had a first boy (died of young age), a girl Isabella (who became a famous duchess of Burgundy and Flanders), then five boys who were grew up under the memories of the famous battle.

Finally, for reasons that would be proven false later, the King declared the Duke of Coimbra a traitor and usurper, called his banners to war and marched against Peter.

The Duke of Braganza called his own banners in support of his nephew the king and joined forces with the royal army near Lisbon, bringing their numbers close to 30 000 men.

Afonso's son, John II, turned his back on Castile and saw an opportunity in the ocean discoveries and expanded them, making Portugal the first intercontinental empire and becoming the most powerful King in medieval history.