History of the papacy (1048–1257)

The history of the papacy from 1048 to 1257 was marked by conflict between popes and the Holy Roman Emperor, most prominently the Investiture Controversy, a dispute over who—pope or emperor—could appoint bishops within the Empire. Henry IV's Walk to Canossa in 1077 to meet Pope Gregory VII (1073–85), although not dispositive within the context of the larger dispute, has become legendary. Although the emperor renounced any right to lay investiture in the Concordat of Worms (1122), the issue would flare up again.

The Imperial crown once held by the Carolingian emperors was disputed between their fractured heirs and local overlords; none emerged victorious until Otto I, Holy Roman Emperor invaded Italy. Italy became a constituent kingdom of the Holy Roman Empire in 962, from which point emperors were Germanic. As emperors consolidated their position, northern Italian city-states would become divided by Guelphs and Ghibellines.

Long-standing divisions between East and West also came to a head in the East-West Schism and the Crusades. The first seven Ecumenical Councils had been attended by both Western and Eastern prelates, but growing doctrinal, theological, linguistic, political, and geographic differences finally resulted in mutually denunciations and excommunications. Pope Urban II (1088–99) speech at the Council of Clermont in 1095 became the rallying cry of the First Crusade.

Unlike the previous millennium, the process for papal selection became somewhat fixed during this period. Pope Nicholas II promulgated In Nomine Domini in 1059, which limited suffrage in papal elections to the College of Cardinals. The rules and procedures of papal elections evolved during this period, laying the groundwork for the modern papal conclave. The driving force behind these reforms was Cardinal Hildebrand, who later became Gregory VII.

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