The hierarchy of the Catholic Church had made many attempts during the Middle Ages to take over Christian Spain politically, such as claiming the Church's ownership over all land reconquered from non-Christians (a claim that was rejected by Castille but accepted by Aragon and Portugal). In the past, the papacy had tried and partially succeeded, in forcing the Mozarabic Rite out of Iberia. Its meddling attempts had been pivotal for Aragon's loss of Rosellon. The meddling regarding Aragon's control over South Italy was even stronger historically. In their lifetime, the Catholic Monarchs had problems with Pope Paul II, a very strong proponent of absolute authority for the church over the kings. Carrillo actively opposed them both and often used Spain's "mixed blood" as an excuse to intervene. The papacy and the monarch of Europe had been involved in a war for power all through the high Middle Ages that Rome had already won in other powerful kingdoms like France.