Papal authority was at its prime during the twelfth and thirteenth centuries where it had both a secular and spiritual role. The early crusades made the Papacy appear even more successful and monarchs, like the Kings of England, would be willing to act for the pope. Boniface VIII's 'Unum Sanctum' was clarification, just before the beginning of the Avignon papacy, of the pope as the ultimate authority and spiritual head of Christendom. …
