He was now one of the most powerful sovereigns of Europe, for besides ruling over Provence and Anjou and the kingdom of the Two Sicilies, he was imperial vicar of Tuscany, lord of many cities of Lombardy and Piedmont, and as the pope's favourite practically arbiter of the papal states, especially during the interregnum between the death of Clement IV.
During the ensuing interregnum he powerfully contributed, at the head of the nobles of Funen and Jutland, to the election of Christian III.
But, although the relation of reason to an external authority thus constitutes the badge of medieval thought, it would be unjust to look upon Scholasticism as philosophically barren, and to speak as if reason, after an interregnum of a thousand years, resumed its rights at the Renaissance.
This duoregnum proved even more injurious to Hungary than the dreaded interregnum.
He returned briefly to cover an interregnum in 1946.