217 Many North Americans view Christianity primarily as a Western religion and are familiar only with its Catholic and Protestant expressions, which have dominated the Western world. Such a view runs against the fact that Christianity emerged in the eastern part of the Roman Empire and had a distinct history in a non-Western world. While this chapter focuses on the distinctive features of Eastern Christianity, it is also important to emphasize that the history of Eastern Christianity, particularly in the first millennium, is closely intertwined with the history of Western Christianity. For example, monasticism emerged in the East and very soon spread to the West. The Ecumenical Councils of the first millennium were held in the East, yet included delegates from all parts of the Roman Empire. The canon of scripture, the structure of the liturgy, and the threefold pattern of church leadership involving bishop, priest, and deacon are complex developments that also belong to a mutual heritage of East and West. While these shared aspects of the Christian theological tradition could serve as a common ground, they have also functioned as causes of divisions.