Humbert of Mourmoutiers (c.1015 – 5 May 1061) was a French prelate, Roman Catholic cardinal and Benedictine oblate, donated by his parents to the monastery of Mourmoutiers in Lorraine. He was invited to Rome in 1049 by the reformer Pope Leo IX, who made him archbishop of Sicily (though the Normans prevented his landing there) and then cardinal-bishop of Silva Candida (1050).

Under Leo, he became the principal papal secretary and on a trip through Apulia in 1053, he received from John, Bishop of Trani the letter from Leo, Archbishop of Ochrid, criticising Western rites and practice. He translated the Greek letter into Latin and gave it to the pope, who ordered a response drawn up. This exchange led to Humbert being sent at the head of a legatine mission with Frederick of Lorraine, later Pope Stephen IX, and Peter, archbishop of Amalfi, to Constantinople to confront Patriarch Michael Cerularius. He was cordially welcomed by the Emperor Constantine IX, but spurned by the patriarch. Eventually, on 16 July 1054, despite the fact that Leo had died and the excommunication was invalid, he laid a Bull of excommunication on the high altar of the church of the Hagia Sophia during the celebration of the liturgy. This event crystallized in an official way the gradual estrangement of Eastern and Western Christianity, and is traditionally used to date the beginning of the Great Schism.

In his later years, he was made librarian of the Roman Curia by Stephen IX, his former legatine companion, and he penned the reform treatise Lib tres adversus Simoniacos ('Three Books Against the Simoniacs') (1057), which helped initiate the Gregorian Reform movement. He is also credited as the brains behind the electoral decree of 1059, which stated that popes would henceforth be elected by the College of Cardinals.

[edit] Sources

• Norwich, John Julius (1967). The Normans in the South 1016–1130. London: Longman.
• Hüls, Rudolf. Kardinäle, Klerus und Kirchen Roms: 1049–1130. Tübingen: 1977. See pp. 133–34.