The Papacy in the 11th and 12th was one of continual turmoil and conflict. The outcome depended largely on the successes of individual popes and individual rulers. Pope Alexander III was pitted against Roman Emperor Frederick I and against King Henry II of England, and Pope Innocent III, despite opposition by Emperor OttoIV and Emperor Frederick II, made himself virtual arbiter of the west.
The struggle between the house of Hohenstaufen and their opponents allowed the papacy to expand its territory in Italy. The Holy Roman Emperor Frederick II sought to consolidate Imperial power in Italy, but was excommunication by the papacy and opposed by the Lombard cities. Frederick’s son Conrad IV continued the struggle with the papacy, but the position of his son Conradin was usurped by Frederick’s second son Manfred, allowing the Pope to declare the throne forfeit and to offer it to Louis IX of France who passed it on to his brother, Charles of Anjou.
The papacy was able to benefit from the weaknesses of its Italian opponents to expand northwards, first into the Duchy of Spoleto and the March of Ancona, and then into Romagna. The Frankish rulers had granted the papacy much of central Italy in the 8th century, but it had proved very difficult for the popes to wield effective control outside the area near Rome, and the lands to the east of the Apennines were in effect independent.
Similar problems arose with the lands bequeathed to the papacy by the Countess Mathilda of Tuscany who died in 1115. Under Innocent III there was a major attempt to give meaning to Papal territorial claims and this was continued under his successors. This was achieved by obtaining Imperial renunciation of territory and by granting papal bulls of protection. The popes began to organise their territory more effectively, creating provinces governed by rectors.
Innocent’s reign (1198–1216) marked the zenith of papal secular power. As a religious leader Innocent worked to reform clerical morals and combat heresy. He ordered (1208) a crusade against the heretical Albigenses in S France that ended disastrously and cast a shadow over his pontificate. A century later Boniface VIII, an able canon lawyer, proved himself no match for the ruthless king of France, Philip IV.
Pope Clement V in 1309 deserted Rome for Avignon and the domination of France. During the so-called Babylonian captivity (1309–78) all the popes were French, all lived at Avignon, and all were under the control of the French kings. The Avignonese papacy represented the culmination of the administrative structure of the church, which reached into almost all corners of Europe.
Pope Gregory XI moved the papacy back to Rome. But the church was immediately plunged into the disorder of the Great Schism (1378–1417). There were two or even three rival popes. The schism ended in the Council of Constance. Since then there has been no schism in the papacy.
Subsequently, the pope had little real power outside Italy, and no 15th-century pope was prepared to attempt serious reform, which would have required challenging the vested interests of bishops, cardinals, and princes. Indeed, in the 15th cent. The papal court made Rome a brilliant Renaissance capital, enriched by some of the finest art of the West. The Renaissance popes, however, were little distinguished from other princes in the extravagance and immorality of their courts.