Catholicism
In 451, a church division happened when all the church leaders meeting at the Church Council in the city of Chalcedon excommunicated (cut off) three leaders, because they held to monophysitism and would not accept the view that Jesus had two natures (fully divine and fully human). These three were the bishops of Egypt, Syria, and Armenia. Of course, these three bishops did not accept being excommunicated either, so the churches under them are still known today as Oriental Orthodox Churches.