Imposed by the Holy Roman Empire to end more than a century of decline, Pope St. Leo IX (1049-1054) was a great reforming pope. Originally from Alsace-Lorraine, he was also the initiator of the Great Schism with the East in 1054.
We are publishing a series on the 13 popes who bore the name Leo before our current pope. Ninth episode: Leo IX (1049-1054) and the Great Schism with the East.
Chaos at the papal court
At the beginning of the 11th century, the Holy See was in the hands of powerful Roman families who fought for control. Despite attempts by Emperor Otto I to end this system, the papacy descended into anarchy after the election of Benedict IX in 1032. This pope, who was in his twenties, was deposed by a rival candidate, Sylvester III, but regained his position and claimed it from his uncle Gregory VI in 1045.
Emperor Henry III then decided to intervene by forcing the Synod of Sutri to be held in 1046, which deposed the three popes. He appointed a German bishop, Clement II, as pope, but he fell ill and was quickly forced to abdicate. Benedict IX attempted a comeback, but Henry III drove him out and appointed another German bishop, Damasus II, who died of malaria after 17 days as pope. As with Clement II, some contemporaries whispered rumors of poisoning.
An austere and pious man, chosen by the emperor
The emperor then turned to his cousin, the Archbishop of Toul, Bruno von Eguisheim-Dagsburg, an austere and pious man known for encouraging the Cluniac reform in the Benedictine monasteries of the Holy Roman Empire.
Guibert of Toul, biographer of the man who took the name Leo IX in 1049, recounts that the bishop of Lorraine tried to refuse the office before finally accepting. Leo IX skillfully had his election validated by the people of Rome. This strengthened his legitimacy and allowed him to initiate a vast program of reform within the Church.
This period of moralization anticipated the “Gregorian Reform,” launched during the pontificate of Gregory VII (1073-1085), as Leo IX drove the movement forward with the support of intellectuals such as the Italian monk Hildebrand of Soano, the future Gregory VII.
To legitimize his actions, Leo IX did not hesitate to leave Rome several times to travel to the West, visiting Reims, Bratislava, and Cologne, among other places, and participating in several synods. He encouraged the Normans and Pisans to fight against the barbarian invasions that had been ravaging the Mediterranean coast for over a century.
The Great Schism between East and West
He considerably strengthened the papacy and armed the Church against heresy and Islam. However, he failed, politically speaking, to impose his will in southern Italy, the lands of the Eastern Roman Empire where the Normans had settled. He was even defeated and taken prisoner by the Normans in 1053. After nine months in captivity, he returned to Rome in very poor health, where he died on April 19, 1054.
But that was not all, because on July 16 of the same year, his emissary to Constantinople, Humbert of Moyenmoutier, took the liberty of placing a bull on the high altar of the Basilica of Saint Sophia excommunicating Patriarch Michael I Cerularius and all his collaborators. In response, the emissary from Rome and his escort were also excommunicated by Michael I: this was the “Great Schism.”
Throughout the pontificate of Leo IX, tensions between the two sides became heated. Michael I, who was very hostile to Rome, had previously condemned the presence of the filioque in the Creed — a theological controversy over the relationship between God the Father and God the Son.
