The Great Schism of 1378 split the center of the papacy between east and west.
The schism of 1378 is also sometimes known as the Western Schism. There were competing popes claiming the authority of that office and the allegiance of Catholics in Europe. The schism began in the years that followed the Avignon period of the papacy, when the papal headquarters had been moved from Rome to the borders of France.
The Great Schism of 1054 included theological issues, but was also a power struggle in the church that led to mutual declarations of excommunication between the pope in Rome and the patriarch of Constantinople. It split the western church (the Roman Catholic Church) from what has become known as the Eastern Orthodox Church. "Catholic" means universal -- the Roman pope was intent on asserting his leadership over all of Christendom. "Orthodox" means "right teaching." The Eastern patriarch and church were asserting their teachings to be right over against positions held in the West. There were a number of doctrinal issues debated hotly between East and West over the centuries leading up to the split in 1054. But more than anything, that split too came down to "church power" -- who held control over the church.
