John was born atMedina del Campo (in theCrown of Castile), the son of KingFerdinand I of Aragon[2] andEleanor of Alburquerque.[3] In his youth he was one of theinfantes (princes) of Aragon who took part in the dissensions of Castile during the minority and reign ofJohn II of Castile. Until middle life he was also lieutenant-general in Aragon for his brother and predecessorAlfonso V, whose reign was mainly spent inItaly.[4] In his old age he was preoccupied by incessant conflicts with his Aragonese and Catalan subjects, withLouis XI of France, and in preparing the way for the marriage of his son Ferdinand withIsabella I of Castile which brought about the union of the crowns of Aragon and Castile and which was to create theMonarchy of Spain. His troubles with his subjects were closely connected with tragic dissensions within his own family.[5]
John was first married toBlanche I of Navarre of theHouse of Évreux.[4] In 1432, John II appointedJuan Vélaz de Medrano, Lord of Igúzquiza and Learza, as his royalchamberlain, a position he had previously held under Blanche's late father,Charles III of Navarre. By right of Blanche he becameking of Navarre, and on her death in 1441 he was left in possession of the kingdom for his lifetime. But one son,Charles, given the title "Prince of Viana" as heir of Navarre, had been born of the marriage. John quickly came to regard this son with jealousy. After his second marriage, toJuana Enríquez, it grew into absolute hatred, being encouraged by Juana. John tried to deprive his son of his constitutional right to act as lieutenant-general of Aragon during his father's absence. Charles's cause was taken up by the Aragonese, however, and the king's attempt to make his second wife lieutenant-general was set aside.[5]
There followed the longNavarrese Civil War, with alternations of success and defeat, ending only with the death of the prince of Viana, possibly by poison administered by his father in 1461.[6] The institutions of thePrincipality of Catalonia, who had adopted the cause of Charles and who had grievances of their own, called in a succession of foreign pretenders in the ten years'Catalan Civil War. John spent his last years contending with them. He was forced to pawnRoussillon, his Catalan possession on the north-east of the Pyrenees, to KingLouis XI of France, who refused to part with it.[5]
In his old age John was blinded bycataracts, but recovered his eyesight with an operation (couching) conducted by his physicianAbiathar Crescas, aJew. The Catalan revolt was pacified in 1472, but until his death in 1479 John carried on a war, in which he was generally unfortunate, with his neighbor the French king. He was succeeded byFerdinand, his son by his second marriage, who was already married toIsabella I of Castile.[5] With his death and son's accession to the throne of Aragon, the unification of the realms of Spain under one royal house began in earnest.
^de Sousa, Antonio Caetano (1735).Historia genealogica da casa real portugueza [Genealogical History of the Royal House of Portugal] (in Portuguese). Vol. 2. Lisboa Occidental. p. 497.
Earenfight, Theresa (2015). "Trastamara Kings, Queens, and the Gender Dynamics of Monarchy". In Todesca, James (ed.).The Emergence of León-Castile c.1065-1500: Essays Presented to J.F. O'Callaghan. Ashgate. pp. 141–160.
Livermore, H. V. (1966).A New History of Portugal (2nd ed.). Cambridge University Press.120
Merriman, Roger Bigelow (1918).The Rise of the Spanish Empire in the Old and in the New. Vol. 2. The Macmillan Company.