What matters for us are the differences between the churches, the main doctrinal one being about the dating of Easter, and the main political one being about who rules whom. Did I get my whom right there, Stan? Yes! In the West, there was a pope, and in the East, there was a patriarch. The pope is the head of the Roman Catholic Church. He sort of serves as God's regent on Earth, and he doesn't answer to any secular ruler. And ever since the fall of Rome, there has been a lot of tension in Western Europe between popes and kings over who should have the real power.