Philip carried several titles as heir to the Spanish kingdoms and empire, including Prince of Asturias. The newest constituent kingdom in the empire was Navarre, a realm invaded by Ferdinand II of Aragon mainly with Castilian troops (1512), and annexed to Castile with an ambiguous status (1513). War across Navarre continued until 1528 (Treaties of Madrid and Cambrai). Charles V proposed to end hostilities with King Henry II of Navarre—the legitimate monarch of Navarre—by marrying his son Philip to the heiress of Navarre, Jeanne III of Navarre. The marriage would provide a dynastic solution to instability in Navarre, making him king of all Navarre and a prince of independent Béarn, as well as lord of a large part of southern France. However, the French nobility under Francis I opposed the arrangement and successfully ended the prospects of marriage between the heirs of Habsburg and Albret in 1541.