"Early Eastern Christianity," the tide which I have given to these six Lectures, may possibly be held to be a misleading name. My Lectures are an attempt to sketch the leading characteristics of the ancient Church of Edessa and the Euphrates Valley from the earliest times to the Council of Chalcedon. The "Eastern Church" in popular usage generally means something geographically wider. We think of Greeks and of Russians, of Alexandria and Constantinople. But compared with the Church about which I have written these names belong to the West, to the great Church within the Roman Empire. It is the unique distinction of the Church of the Euphrates Valley, that alone among the developments of Christianity in the ante-Nicene age it had some of its roots in a realm outside the Roman Empire, and that the language of its learning and its aspirations was a tongue akin to that of Palestine.