Imperial Neighbours: the East

The empire’s most significant neighbour on the eastern front was the Sasanid Persian empire. Established in 226 CE upon the overthrow of the Parthian Arsacid dynasty, the Sasanid kings created a powerful state that rivalled the Roman empire, challenging Rome for control of the Syrian desert and the cities of northern Iraq and Syria, as well as for influence in the Arabian peninsula and as far afield as the Horn of Africa and Ethiopia. With commercial and political contacts in northern India, the Indian Ocean and China, the Sasanid realm was a major international power with a vibrant culture, dominated politically by Zoroastrianism, but in which Nestorian Christianity in particular came to play a key role after the middle of the fifth century. Relations with Rome throughout the history of the Persian empire were tense - while there were substantial periods without actual fighting, the Romans were always aware of the threat from the east and substantial resources were devoted to holding it in check. By the same token, the Persians likewise spent considerable sums in protecting their own frontier and in challenging Rome for control over the mountainous Armenian principalities and lesser Caucasian states, both because of their strategic significance and because of the wealth of their mineral resources, in particular gold and other precious metals.

The central and southern sectors of the eastern Roman frontier were protected, or at least covered, by the great Syrian desert which stretched down into the Hejaz, and by the Sinai desert. These were by no means impassable, but nevertheless meant that major routes into the empire were few and well-used. The desert was reinforced as a barrier and frontier by the garrisons of the limes diocletianus. The semi-nomadic populations of the northern Arabian peninsula occasionally posed a threat as small-scale raiders, but were also a source of mercenary and allied soldiers who could be employed against the Persians; while the commercial centres of the southern coast or the north, such as Medina and Mecca, maintained regular trading contacts between the cities of Syria and Palestine, the Indian Ocean, the east African littoral and the Axumite kingdom of Ethiopia. The frontier with the Arabs remained stable from the fourth to the seventh centuries. A system of allied tribes or clans organised as foederati, or federates, under a paramount group (the Tanukhids in the fourth century, the Salihids in the fifth, and the Ghassanids in the sixth and seventh centuries) served to defend Roman interests, and by the time of Justinian the Ghassanid kings were thoroughly integrated into the east Roman system of precedence.

The Arabian peninsula, and especially the organised states of Aden and the Yemen, were also a focus for Roman diplomatic activity, especially in view of their closeness to the Christian state of Ethiopia. The east Roman rulers regarded the kingdom of Axum (named after the capital city, in the north Ethiopian highlands) as a legitimate part of their sphere of influence, although the Axumite rulers themselves remained entirely independent. Christian since its conversion in the fourth century, it depended ecclesiastically on the patriarch of Alexandria, and was heavily influenced by the Syrian monastic tradition. The Axumite kingdom was a key player in Roman politics in the Arabian Peninsula-Red Sea region, and during the wars in the kingdom of Himyar in the period 517-537 its emperor, Kaleb ’Ella ’Asbeha, had actually invaded and occupied the region at the request of the Emperor Justin I. Himyar itself was a bone of contention between Persia and Rome - in the 520s the independent ruler Dhu Nuwas challenged Roman influence and, seen as a threat to trade and east Rome’s international position, was crushed when the empire’s Axumite allies invaded, as noted already.

The Himyarite kings remained tributary to Axum, but under Justinian, a serious conflict for influence between the Sasanids and the Romans developed. But although the emperor attempted to bring the Himyarites into the conflict on the Roman side, they played for the most part a neutral game until, in the early 570s, a Persian force was invited in by some of the subordinate chiefs, the king was slain in battle, and Persia became the pre-eminent power in the region. Thereafter relations between the Jewish communities and the (monophysite) Christians in Himyar were stabilised until, in the 620s, Mohammed dispatched his initial call to the people of the region to embrace Islam, which quickly became the dominant belief system in the region.

The northern sector of the east Roman frontier in the east was occupied by the Armenians, Georgians and other, minor, Caucasian principalities. Georgia (Greek Iberia, Georgian K’art’li) was divided into two zones, the eastern (Iberia proper) and the western (also called Lazica, later divided into a northern section - Abkhazia - and a southern - Lazica). Converted to Christianity in the fourth century, Georgia remained closely tied to the east Roman and Byzantine worlds, politically and ecclesiastically, breaking with the orthodox (Chalcedonian) tradition at the Council of Dvin in 505, but returning to the east Roman fold in the early seventh century. A source of minerals as well as of soldiers, but in particular a region of strategic significance, west Georgia - Lazica and the coastal region of Suania - became the object of hard-fought campaigns between Roman and Persian armies during Justinian’s reign, in a conflict which lasted from 542 until 556. East Georgia - Iberia - was similarly fought over, and occupied by the Persians in 522-523, who installed their own military governor or marzban.

Armenia, which had likewise become Christianised during the fourth century, had been divided into three sectors: west of the Euphrates an area under direct Roman control (Armenia Minor), to the east the kingdom of Greater Armenia, and in the south the so-called Satrapies. From the 390s this arrangement was altered: the Romans retained control of the western segment

Map 2.6 Imperial neighbours: the east

And were able to extend their control across the westernmost districts of the kingdom, while the remaining regions of Greater Armenia became part of a Persian-dominated zone referred to as Persarmenia, governed by a military governor appointed by the Persian Great King. Under Justinian, the Armenian regions were reorganised and associated with districts separated from adjacent provinces to form four imperial provinces, Armenia I-IV The successful Roman intervention in the Persian civil war in 590-591 gave the Emperor Maurice the opportunity to negotiate an expansion of Roman control in the region; but Roman attempts to force the Armenian (monophysite) church back into the Constantinopolitan orbit met with resistance at all levels, and made Roman domination extremely unpopular with the majority.

While Maurice had become a close ally of the restored Great King Chosroes II, Maurice’s murder in 602 gave the Persian ruler the opportunity to intervene in Roman affairs.

Ostensibly intending to restore the dynasty of his former ally, Chosroes’ armies invaded the eastern provinces of the empire on a grand scale, harrying imperial provinces in Anatolia and permanently occupying Syria, Palestine and Egypt. Jerusalem fell in 614, Roman Mesopotamia had been conquered by 615, Egypt by 616. A permanent Sasanid administration was set up with military governors for the different provinces. Heraclius’ overtures to restore the status quo ante, on the grounds that he had defeated and killed Phocas, fell on deaf ears: Khusru aimed at nothing less than the re-establishment of the ancient Achaemenid realm of the days of Darius and Xerxes. In spite of the threat from the Avars in Europe and the trouble with the Lombards in Italy, Heraclius launched a brilliant campaign against the Persians in 622. Refusing to be distracted by the great siege of Constantinople in 626,when Persian forces occupied much of north-western Asia Minor in support of the Avar Khagan, Heraclius was intent on taking the war directly onto Persian territory, where he outmanoeuvred the enemy commanders, sacked key Persian fortresses and cult centres and forced Chosroes to flee his capital at Ctesiphon. With Chosroes’ assassination the war came quickly to an end. By 629 the Persian forces had withdrawn from the conquered territories, a new Persian ruler had been put in place under Roman protection, and the great Sasanid empire became for a short while tributary to Constantinople. But even as Heraclius triumphed, unexpected new developments were occurring in the Arabian peninsula which were to transform the late ancient world and its empires for ever.