Founded by William of Aquitaine 909
1046: Council of Sutri: Emperor Henry III (1039-1056) deposes three rival popes (Popes Benedict IX, Silvester III and Gregory VI). Henry nominates Pope Clement II (1046-1049)
Emperor Henry III nominates St. Leo IX (Bruno of Egisheim) 1049-1054
Pope Leo IX holds church councils in Northern Europe that dealt with simony and clerical marriage; asserts papal primacy
Pope Leo IX raises an army in 1053 and led it against the Normans who had been encroaching upon the lands claimed by the Papal States. The papal army was soundly defeated; Pope Leo was held prisoner by the Normans for 9 months. Leo died shortly after his release.
1059 Election Decree of Pope Nicholas II (1058-1061): Cardinals elect the pope
Pope Gregory VII's Decretal forbidding Investiture 1073
Pope Gregory VII's Decretal against Simony and Clerical Marriage 1074