orig. Bruno, count von Egisheim und Dagsburg
born 1002, Egisheim, Alsace, Upper Lorraine
died April 19, 1054, Rome; feast day April 19
Pope (1049–54).
He was consecrated bishop of Toul in 1027. He was named pope by Emperor Henry III but insisted on election by the clergy and people of Rome. His efforts to strengthen the papacy and eradicate clerical marriage and simony laid the foundation for the Gregorian reform movement. His assertion of papal primacy and his military campaign against the Normans in Sicily (1053) alienated the Eastern church. His representatives excommunicated the patriarch of Constantinople. Though Leo had already died, their act triggered the Schism of 1054 .