The Church of the EastChurch of Babylon or Nestorian Church is the second largest of the Christian sects in the world, and for a long time was the largest of them all. This church is one of the largest churches in the world, territory-wise, with dioceses all the way from Western Mesopotamia to Japan, although it's only a majority religion in the northernmost Middle East and parts of Central Asia. There are also large minorities in most of the New World.