We often tend to think of ancient and medieval Christendom principally as Roman and Byzantine (or Catholic and Orthodox) with only a few scattered ‘Oriental’ communions at the margins. But, in the early Middle Ages, the largest (or, to be more precise, most widespread) Christian communion in the world was the Syrian Nestorian Church, also called the East Syrian or Assyrian Church, or (more simply) the ‘Church of the East’.
