Spanish conquest of the Iberian part of Navarre was commenced by Ferdinand II of Aragon and completed by Charles V in a series of military campaigns extending from 1512 to 1524, while the war lasted until 1528 in the Navarre to the north of the Pyrenees. Ferdinand the Catholic was in 1512 both king of Aragon and regent of Castile. When Pope Julius II declared a Holy League against France in late 1511, Navarre tried to remain neutral. Ferdinand used this as an excuse to attack Navarre, conquering it while its potential protector France was beset by England, Venice, and Ferdinand's Italian armies.