Cardinal Humbert declared Michael Cerularius to be excommunicated. Michael was the Patriarch of Constantinople. Michael walked out of the church, shook the dust off of his feel, and left. This event marked the beginning of the Schism, division, between the Greek and Latin Churches. In Southern Italy, Norman warriors conquered the region and Greek (Eastern) Bishops were replaced with Latin (Western) Bishops. People argued about the form of liturgy, differences in marriage, days of fasting, bread used for the Eucharist, and other things.