Peter of Coimbra (also known as Peter the Constable) (Portuguese: Pedro, pronounced [ˈpedɾu]; c. 1429 – Granollers, 30 June 1466) was the son of Infante Peter, Duke of Coimbra, who became the fifth Constable of Portugal and third Grand Master of the Order of Saint Benedict of Aviz.The Consell de Cent later granted Peter the crown of Aragon, which he claimed from 1463 to 1466 in opposition to John II.