The Consell de Cent later granted Peter the Crown of Aragon, which he claimed from 1463 to 1466 in opposition to John II.

[1] Peter inherited a claim to the Aragonese throne through his maternal grandfather James II, Count of Urgell, who was the last male descendant of the House of Barcelona and heir to the Crown of Aragon by the rights of agnatic primogeniture.

[4] This political move, along with Afonso V's marriage to Isabella of Coimbra, Peter's sister, instead of the granddaughter of the Duke of Braganza, caused significant conflict between the two parties.

Afonso V, because of influence of the Duke of Braganza, who became the political enemy of Peter's father, voided all laws created under Coimbra's regency.

[9] In 1456 or 1457, Peter reconciled with King Afonso V and the Duke of Braganza, thus allowing him to return to Portugal and reclaim all his family's previous possessions.