What caused the Christian church to split in 1054 AD?

Answer 1

The view held by religious authorities in the mainly Greek-speaking eastern regions was that there were 5 senior leaders, or Metropolitans, in the Christian Church, one of whom was the bishop of Rome. However, the bishop of Rome, known in the West as the Pope, insisted that he had greater authority than the other Metropolitans. Gradually, differences built up, but the key points of difference were an attempt by the bishop of Rome to change the Nicene Creed without a further Council of bishops, and Rome's objection to the Eastern churches allowing married priests.

The Great Schism resulted when Pope Leo IX sent legates to Patriarch Michael I, they attempted to excommunicate Michael and he then excommunicated the legates (Leo having died, Michael was unable to excommunicate him). There were attempts at reconciliation and the Churches came close to being reunited in 1274 and in 1439, but the schism eventually became permanent.

The western Church, based on Rome, has become known as Roman Catholic, while the eastern Churches have become known as Orthodox Churches.

Catholic AnswerThe Schism of the East has been a long tragedy mostly caused by politics and outside interests.

from A Catholic Dictionary, edited by Donald Attwater, Second edition, revised 1957

The Schism of the East the estrangement and severance from the Holy See of what is now called the Orthodox Easter Church was a gradual process extending over centuries. After a number of minor schisms the first serious, though short, break was that of Photius; from then on tension between East and West increased, and the schism of Cerularius occurred in 1054. From then on the breach gradually widened and has been definitive since 1472. There was a formal union from the 2nd Council of Lyons in 1274 until 1282, and a more promising one after the Council of Florence from 1439 to 1472. After the capture of Constantinople it was in the Turkish interest to reopen and widen the breach with the powerful Roman church; the patriarchates of Alexandria, Antioch, and Jerusalem were dragged into this policy, Russia and the Slav churches stood out the longest of any: none of these churches, except Constantiople itself in 1472, formally and definitely broke away from the unity of the Church. But in the course of centuries the schism has set and crystallized into a definite separation from the Holy See of many million people with a true priesthood and valid sacraments. The origins, causes and development of the schism are matters of much complication, still not fully unraveled.

Answer 2

probably because people in Western Europe refused to recognize the authority of the pope

Answer 3

the eastern orthodox refused to accept the pope as sole head of the christian church