July 26, 1471: Pope Paul II dies in Rome. A few days later, Pope Sixtus IV is elected. It is time to unblock the situation of the bull of Isabel and Fernando. John II of Aragon sends his faithful Pierres Peralta to speak with the new Pope. The influence of Aragon in Italian territories is of prime interest to Sixtus. Also, the provision of funds and the idea of an anti-Turkish crusade. Peralta brings economic congratulations (barely removed from the depleted arcas Aragonese: it is a bet to all or nothing face the future) to Sixto and tells him that he will always have Aragon in everything ... in exchange for the papal bull of marriage of his son Fernando with Isabel. Sixto accepts: it's time to change. For this, he asks for advice from a cardinal he knows well as being Valencian (and belonging to the Kingdom of Aragon). Rodrigo de Borja. And he sends it to Castilla y Aragón to know the problems firsthand.