Shapur II); his successor Jovian (363–364) had to conclude a disgraceful peace, giving up Nisibis and all the provinces beyond the Tigris (363). There were, of course, intervals, sometimes long intervals, of peace, during which the Emperor sent friendly embassies to his brother the King of Kings. But, speaking generally, the background of the story of Eastern Christianity during the first five or six centuries is this eternal struggle between Rome and Persia; behind our theological discussions, synods and bishops, we see tramping legions and flames of burning cities. It might have gone on indefinitely. Would either power ever have worn the other out? Each had worn itself out when, in the 7th century, a new factor entered the scene and swept them both away. Mohammed died in 632. Almost immediately his followers burst upon the Roman Empire in Syria and Persia. Khalid[1] led a Moslem army against Hīra, an Arab state dependent on Persia; then under Sa‘ad Ibn Wakkās they conquered Chaldea and Mesopotamia; ten years later at Nehāwand they won the "Victory of Victories" which made them masters of all Persia (642). The last Sassanid king (Yazdagird III, 632–651) fled and was murdered by wild Turks; the Khalif's power was established in Iran and spread to the land beyond the Oxus. Meanwhile, with equal success the Arabs were tearing provinces from Rome. In 634 they invaded Western Syria. They took Bosra, then defeated the Roman army at Ajnadain (July 30, 634). At Yarmūk the Romans again suffered a crushing defeat (Aug. 23, 634). Damascus fell in 635, and Emesa the next year (636). In 637 Omar, the second Khalif, entered Jerusalem; in 638 Aleppo and Antioch were taken.[2] So from now the situation changes. The old quarrel of Rome and Persia has come to an end, the people so long bandied about between different masters are new ruled by the Moslem Khalif. After the Arab conquest there is little more political history to tell. Till 750 the Khalifs of the house of ‘Umaiyah reigned at Damascus; then they were succeeded by the long line of Abbās at Bagdad.[3] This
