 He managed to overcome the resistance of the Aragonese "Cortes" and Catalan "Corts", and he was finally recognized as king of Aragon and count of Barcelona jointly with his mother.The Kingdom of Navarre had been invaded by Ferdinand of Aragon jointly with Castile in 1512, but he pledged a formal oath to respect the kingdom.On Charles's accession to the Spanish thrones, the Parliament of Navarre ("Cortes") required him to attend the coronation ceremony (to become Charles IV of Navarre), but this demand fell on deaf ears, and the Parliament kept piling up grievances.