“The best sources of military manpower for the defense of Syria, Palestine, and Roman Mesopotamia in the early seventh century were: (1) Arab beduin on the periphery of the empire, although many Arabs were also settled in the towns and villages, and (2) the Armenians.
The Roman army was not large in size, and it was poor in discipline, toughness, and combat experience and readiness. More important, its effective mobile striking forces were modest. It could ill afford to commit more than 20,000 of these for major eastern campaigns. Equally uncertain are the numbers of new recruits. Roman positions in Africa and Italy were under almost constant threat, so they could serve as no source for soldiers, and actually competed with the eastern frontiers for manpower. They needed reinforcement themselves. There was no alternative, in short, to seeking military manpower for Syria, Palestine, and Mesopotamia from nearby and reliable Armenia and especially from Arab beduin, who had the added advantage of familiarity with the local terrain, climate, and military methods of the empire’s potential enemies.
Roman policies toward the Arabs before the 630s remain obscure. The rebellion of the Ghassanids, who had been Roman federated allies, after Maurice’s very imprudent arrest and exile of their phylarch al-Mundhir in 581 and the termination of their subsidies, and the slaying of Nu’man III b. al-Mundhir, King of the Lakhmids, in 602, somehow with the connivance if not explicitly on the orders of Chosroes II, had demonstrated the perils of antagonizing hitherto friendly Arab tribal groupings while they had given Arabs relatively recent examples of the perfidy of rulers of empires and additional reason to be wary of their intentions. It was important for the Empire to retain the friendship of at least some of the tribes. But those events had taken place more than a half-century earlier, and their memory would have existed for some Arabs (perhaps Arabs both inside and outside the Roman Empire) and for some Roman officials at various levels of authority and rank. Only Monophysite histories mentioned the rebellion of al-Mundhir; court histories such as Theophylact’s omitted that embarrassing subject, even though knowledge of it might have helped Heraclius and his advisers make more intelligent decisions. Whether or not the Romans approached the Ghassanids for some kind of restoration of relationships in the reign of Phocas or Heraclius, the fact is that they and their last king, Jabala b. al-Ayham, were foremost among the allied Arab tribes of the Empire in the early 630s. The Romans diversified their relationships with the Arabs by also drawing on other friendly tribes.
The policy was perfectly consistent with the Empire’s preferences and practices in the search for internal and external security in other areas of the empire and in other situations and crises. What precisely the relationships of the Romans were with any of these tribes, however, remains, like the number of their effectives, unclear. Arab manpower was often recruited in groups from specific tribes, with such soldiers retaining their tribal affiliations and identity; they were not simply individual recruits.
Less clear is the relationship between Arab nomads beyond the Roman frontier with the settled population on the land and in the towns inside the frontier. In the centuries previous to the Muslim conquest, that relationship had fluctuated between armed conflict and peaceful mutual dependence and support. But the Roman army did not maintain costly bases and responsibilities for nothing, especially in an era of great fiscal pressures.
Nomadic and sedentary populations were not always in violent conflict on the Transjordanian, Syrian, and Mesopotamian frontiers. A principal function of the late Roman troops who were stationed there was enforcement of the Empire’s authority, the monitoring of tribal movements, and the prevention of nomadic raiding. There unquestionably was at least intermittent interdependence and mutualism. But the Empire did not commit hard to obtain, expensive, crack troops to posts there merely to observe pastoral activities. The quality of the elite troops who garrisoned some posts probably deteriorated during the course of their stationing, but their assignment to this region involved major real costs to the government and presumably was not decided lightly. Those expensive troops had military functions. Behind them lay a genuine fear of potential damage to settled areas and their populations and to the integrity of Roman authority. One should not assume constant warfare, but those Roman troops had genuine military functions. They were not mere symbols. They were expensive commitments of good troops, which the government, if it could, would have gladly moved to some other hard-pressed and exposed frontier. Military force at a considerable financial cost helped to contribute some order to the edge of human habitation.
The Romans also used sedentary Arabs in southern Palestine to protect that region from raids by hostile beduin in the late sixth century. Camps of friendly Arabs on the outer perimeter of the region of important towns had potential military significance for the security of those cities. In seventh-century Roman Syria at the time of the Muslim conquest there was a camp, or hadir, of Arabs near Hims or Emesa, and other such camps appear to have existed in northern Syria. It is uncertain how many camps of allied beduin existed near other major Roman towns on the edge of the desert at the beginning of the 630s such as the hira, that is, an encampment that the Roman client Arabs had formerly used as their base for guarding the approaches to Gaza. The Imperial government obviously had become dependent upon them because they were perceived to be less expensive and more effective and more available than alternative military manpower. Such Arab camps appear to have been a critical element in the defenses of such towns. They helped to substitute for the lack of military training of the towns-people, and they probably were expected to provide information and supply guards for travelers as well as serve as stationary guards of these towns and their neighboring villages and countryside. At one of the earliest Imperial battles against the invading Muslims, that of Ajnadayn, the Romans depended very heavily on local Arabs for provisions.”
(Source: “Byzantium and the early Islamic conquests”, by Walter E. Kaegi)
NovoScriptorium: We have replaced the term ‘Byzantine’ used in the original text to the actual historical one, which is simply and only ‘Roman’. We also used the terms ‘Imperial’ or ‘the Empire’. Nothing else is changed from the original text.
Research-Selection for NovoScritorium: Anastasius Philoponus