In the summer of 260 the Persians under Shapur I routed a large Roman expeditionary force near Edessa, captured the emperor Valerian (253-260) and many of the officials in his entourage, and once again were in a position to devastate the cities and villages of the Roman east. [70,000 strong, according to the Persian account] As in 244, when the praetorian prefect Philip replaced Gordian III (238-244), who had been mortally wounded in the debacle at Misike, the Roman survivors rallied round two of their commanders, Macrianus and Quietus, and staged a desperate, and apparently ineffective, counterattack against the Persian rearguard. Confronted now by rebellions in both east and west, Valerian's son Gallienus (253-268) was in no position to contest the Persian occupation of Osrhoene and Mesopotamia, the cockpit of the geopolitical struggle between Rome and Persia, or to engage personally in negotiations to liberate Valerian and his retinue. He might have embarked on such a rescue mission the following summer, after his generals had defeated Macrianus in Thrace, but instead he entrusted the administration of the Roman east to Odenathus, the Palmyrene princeps, who defeated the rebel remnant in Syria and governed in the emperor's name with the title corrector totius orientis.
Odenathus is said to have conducted several offensives against the Persians, but there is no reason to believe that he managed to recover Osrhoene and Mesopotamia. Nor was this the primary objective of his wife Zenobia, who succeeded (with Vaballathus) when Odenathus and one of his sons were assassinated at Emesa in 267/268. Over the next four years, in fact, Zenobia constructed an alternative and independent regime in Palmyra and in successive engagements with the legions stationed in Arabia and Egypt (270) challenged what remained of Roman authority in the east. That she had neither the resources nor the popular support required to withstand a determined Roman assault, however, was demonstrated when Aurelian, within a few months of his arrival (272), defeated Zenobia's army in the field (at Immae and Emesa) and captured Palmyra. Aurelian's immediate departure for the west meant that this decisive victory, the first by Roman troops in the east for a generation, was not the prelude to the restoration of the Roman frontier that Septimius Severus had created. In spite of Aurelian's assumption of the title Persicus Maximus, for more than a decade Osrhoene and Mesopotamia would remain in Persian hands.
The campaign that Carus (282-283) launched in 283 was the first direct assault on Persian hegemony since the capture of Valerian. This initiative seems to have been prompted by the report, received while Carus was engaging the Sarmatians, of a serious internal challenge to the authority of the Persian monarch, Vahram II. Details are sketchy but it is clear that the campaign was surprisingly successful - resulting in the capture of Seleucia and Ctesiphon - and was interrupted only when Carus, encamped on the Tigris, was struck by lightning and died. The fate of his son and successor, Numerianus (283-284), is uncertain. One tradition reports that he was defeated and captured by the Persians; another that he was assassinated on the Roman retreat by Aper, his father-in-law and praetorian prefect. All one can say for certain is that the Roman army did withdraw to Asia Minor, transporting Numerianus or his corpse, and at Nicomedia on 20 November 284 proclaimed Ciocles, then in charge of the protectores, as the new Augustus. By the following spring/summer Diocletian had eliminated his rivals, Aper and Carus' surviving son, Carinus (283-285), and had selected Maximianus as Caesar.
In 287 the new Augustus negotiated a modus vivendi with the Persians that installed Tiridates III as the ruler of Armenia. It was this negotiated settlement that Diocletian - rector orbis, fundator pacis aeternae, Persicus maximus - advertised as a victory over the Persians in an inscription dated to 290. It was not to last. Soon after he came to power in Persia in 293, Narses repudiated the agreement and invaded Armenia to expel the Roman client. It was this fresh threat, according to the literary accounts, that persuaded Diocletian to nominate Galerius and Constantius as Caesars.
Galerius'first major assignment, Barnes has persuasively argued, was in Egypt, where he conducted a campaign in 293/294 agaisnt Coptos and Busiris, which had rebelled, and destroyed both towns. [T. Barnes, "Imperial Campaigns, A.D. 285-311," Phoenix, XXX/1976, 174-193] These achievements were lauded in a panegyric of 1 March 297 and celebrated years later in his assumption of the titles Aegyptiacus maximus, Thebaicus maximus. The campaign itself is further attested in a papyrus of January 295 which mentions two protectores Augustorum and several praepositi of legionary detachments which participated - among those identified are three Moesian units: IV Flavia, VII Claudia, and XI Claudia. The presence of the protectores is testimony of Diocletian's concern for the safety, and good behavior, of the new Caesar on his first outing, as one would expect from an Augustus and former commander of the protectores. The detachments from the three Moesian legions, whose loyalty to the new regime would have been unshakable, may have ben members of Galerius' comitatus and probably accompanied the Caesar on his subsequent assignment in Syria, the campaign against the Persians.
Whether Diocletian was personally involved in the first Persian campaign in 297 is uncertain - the significance that Barnes attached to a papyrus fragment of a contemporary epic poem must be weighted against the unanimous literary tradition that Galerius had ben entrusted with the command. Nor is it important here. That the first campaign, evidently conducted entirely in Mesopotamia womewhere in the familiar killing fields between Carrhae and Callinicum, ended with a decisive Roman defeat is clear enough. Preparations for a return bout are said to have begun at once, but the recruitment of fresh troops from the Balkans may well have continued into 297. This time indisputably in charge of operations, Galerius wisely conducted the second campaign through Armenia and by mid-298 "had trod underfoot the quivers and arrows of the Persians." By the time Diocletian returned to Antioch from Egypt in February 299, Galerius was engaged in negotiations with Narses at Nisibis and had the clear edge owing to the Roman capture of the Persian harem.
The treaty that Galerius negotiated, and Diocletian approved, defined Roman-Persian relations for the next 60 years. Both Festus and Ammianus Marcellinus refer to the treaty, but it is Petros Patrikios who provides the most detailed account of the terms.
1. Nisibis became the obligatory "trading post" for the two
empires; [perhaps a replacement for Palmyra]
2. The Tigris was established as the political boundary between Rome and
Persia;
3. All the territory betwen the Euphrates and the Tigris (Mesopotamia,
Osrhoene, and Armenia) came under Roman control;
4. Persia agreed that the regiones Transtigritanae - five Armenian
satrapies, or nine if one accepts winter's reading of the texts - should
become Roman dependencies.
In short, through the treaty rome recovered all the territory claimed by the Severans - with the addition of the regiones.
this much is clear, but how Diocletian and Galerius intended to organize and administer this territory is not. They did not attempt to occupy the regiones, which came into play only under Constantius, and were content (at least Diocletian is thought to have ben) to recognize the Tigris as the official political boundary. Similarly, no attempt was made to administer Armenia directly. It simply reverted to the dependent status Diocletian had sought to secure in 287. Although the victors presumably were free to do as they wished in Mesopotamia and Osrhoene, the archaeological evidence from these once and future provinces does not attest the deployment of new units or the construction of new military outposts. Further discoveries may be made, but at present nothing on the ground suggests that Mesopotamia was protected by the network of praetenturae and stationes agrariae that Ammianus Marcellinus observed in 354. Nor is there any trace of the interiores limites, in ipsis barbarorum confiniis, that Ammianus attributed to Diocletian. Troops presumably were stationed once again in Nisibis and other major cities, but in the vast countryside only the fort at Cercusium, at the confluence of the Euphrates and the Khabur, can safelly be credited to Diocletian. Though the treaty was unquestionably a turning point in the geopolitical struggle, it apparently did not lead immediately to the reoccupation of forts constructed by the Severans in Mesopotamia and on the Tigris. [G. Algaze, R. Breuninger, C. Lightfoot, M. Rosenberg, "The Tigris-Euphrates Archaeological Reconnaisance Project: A Preliminary Report of the 1989-1990 Seasons," Anatolica XVII, 1991, 175-254]
What, then, is one to make of the praesidia and castra associated with the Strata Diocletiana and the system of branch roads between the Euphrates and the Gulf of Aqaba? Is this not definitive evidence of "an unprecedented level of military construction" along the "desert frontier" that Zosimus, Malalas, and many modern scholars attribute to Diocletian? Before we turn to the purpose of the network it may be useful to review the evidence of road construction and troop deployment in this zone, much of it produced or supplemented by recent surveys and excavations. [Please use the maps distributed in class as you read these sections].
(1) The network was in fact an amalgam of road construction over two centuries: only the Strata Diocletiana in the Palmyra region and the branch road between Bostra, the capital of Arabia, and the oasis at Azraq can be securely credited to Diocletian. Whether the branch of the Strata running along the eastern edge of the Jebel Hauran, from Dumayr to Azraq, was originally laid out by the Severans or constructed under Diocletian is uncertain. From Damascus to Boastra there were two routes: across the lava fields of the Leja (constructed during the 2nd century) and from Dumayr via Shaqqa (normallly attributed to Septimius Severus). From Bostra south to Aila the road ws the Via Nova that Trajan constructed after the annexation of Arabia. [see D. Graf, "The Via Nova Traiana in Arabia Petrea," in The Roman and Byzantine Near East: Some Recent Archaeological Research, Ann Arbor, 1995, 241-267.]
(2) The placement of praesidia and castra along the roads marks a significant change in the deployment of troops. Diocletian abandoned most of the legionary camps used by his predecessors - Apamea, Raphanaea, Emesa, Zeugma, and Samosata; only Bostra continued in service - and stationed his legions, much reduced in strength, in forts situated on or adjacent to the roads: at Sura, Orisa, Palmyra, Danaba, Lejjun, Udruh, and Aila. Associated with the legions, within 20 km. of the roads, were the numerous smaller posts of the auxiliary units attested in the Notitia dignitatum rosters.
The purpose of this integrated road network has been vigorously debated. Was it a limes Arabicus, designed to repel the raids of neighboring gentes (the desert folk known collectively from the fourth century on as the Saraceni), as Parker has repeatedly argued? [S. T. Parker, Romans and Saracens: A History of the Arabian Frontier, Winona Lake, 1986]. Or were the unis stationed along the road to provide security for travellers and to maintain police activities required "by any power that aims at controlling desert areas"? [B. Isaac, The Limits of Empire: The Roman Army in the East, Oxford, 1992]. The central question, fundamental to both hypotheses, is whether the Saraceni had become a sufficient threat - not simply an occasional irritant - to require the construction of an elaborate system of defence.
The first literary reference to Saraceni appears in a panegyric of 291, in which the orator praises Maximian for his recent "enchainment of the Sar(r)aceni" - an unlikely achievement for the western Augustus. A few paragraphs on the orator also congratulates Diocletian for his victory over the nationes on the borders of Syria (de victis accolentibus Syriam nationibus). Although the Saraceni are not mentioned, and the victory was never formally recognized in the titulature of Diocletian, modern scholars have reasonably assumed that the orator is referring to the same event - a "Saracen Campaign" that Diocletian conducted during his brief stay in Syria in 290. Unfortunately neither reference provides a clue to the location of these Saraceni or the circumstances that led to their suppression.
Some have detected confirmation that this was not an isolated event, but the first in a continuing series of Roman responses to a rising "nomadic threat", in a recently rediscovered inscription from the oasis of Azraq/Basienis: [first published by D. Kennedy, Archaeological Explorations in the Roman Frontier in North East Jordan, Oxford, 1982, 179 ff; and here in an improved version, by M. Speidel, "The Roman Road to Dumata (Jawf in Saudi Arabia) and the Frontier Strategy of Praetensione Colligare," Historia, XXXVI, 1987, 215.]
[...............................................
................................................]
per mil(ites) fortiss(imos) suos
legg(ionum) XI K(laudiae) et VII K(laudiae)
et I Ita(licae) et IIII Fl(aviae) et
I Ill(yricorum), praetensione
coligata mil(itibus) suis ex
leg(ione) III Kyr(enaica). A Bostra
Basianis m(ilia) p(assuum) LXVI et
a Basienis Amat(a) LXX
et ab Amata Dumata
m(ilia) p(assum) CCVIII.
...by his most valiant soldiers of the legions XI Claudia and VII Claudia and I Italica and IV Flavia and I Illyricorum, linked by manned posts [Speidel's proposed translation]to his soldiers from legion III Cyrenaica. From Bostra to Basianis 66 miles and from basienis to amata 70 miles and from Amata to Dumata 208 miles.
As the inscription is acephalous (the first two lines of text are missing), the identity of the emperor addressed cannot be determined. an approximate date is provided, however, by the units assembled at Azraq. With the exception of local units ( I Illyricorum from Palmyra, III Cyrenaica from Bostra) these were detachments of the same Moesian legions active in Galerius' Egyptian campaign: IV Flavia, VII Claudia, and XI Claudia (I Italica may, or may not, have been part of the expeditionary force in Egypt). As Kennedy has suggested these units probably arrived with Galerius in 295 and stayed on to participate in the campaigns against the Persians in 296-298. If so, then their activities at Azraq would have had nothing to do with the Saracen campaign of 290, whatever its dimensions.
Whether these units were employed in the construction of roads in the region, were stationed for an extended period in Azraq/Basienis, or were simply patrolling the area around the oasis cannot be determined from the text. This was not the first time that Roman troops had visited Azraq or the first expression of imperial interest in the famous transhumant route from Dumata/Jawf. [See G. W. Bowersock, Roman Arabia, Cambridge, Mass, 1983, 98]. The appearance of Dumata in the inscription, however, does not prove that a roman road extended as far as Dumata or that there were Roman posts along its length. The only sites "linked by manned posts" were Bostra, where the legion III Cyrenaica was stationed, and Azraq. Nothing in the text, moreover, suggests that these "manned posts" were connected with roman operations against a rising "nomadic threat" in southern Arabia, or that the units at Azraq had been subjected to "ambushes" of the sort attributed to the Saracens in an inscription of 334 from a nearby road station. As many modern scholars have emphasized, before the reign of Diocletian such attacks were invariably local in origin and scope and were not associated with major nomadic migrations or incursions. [see D. Graf, "Rome and the Saracens: Reassessing the Nomadic Menace," in T. Fahd (ed), L'Arabie preislamique et son environnement historique et culturel, Leiden, 1989, 350]. In the absence of firm evidence that conditions in the desert or among the Saracens had fundamentally changed during the closing decade of the third century, which neither the Panegyric nor the Azraq inscription attests, Speidel's assertion that the function of the Dumata praetensio [sic] was "to forewarn the legion at Bostra about gathering attacks by the Saracens or Persians" must be considered pure speculation.
It is far more likely, in my judgment, that it was Diocletian's determination to restore the Roman east, and not some putative "nomadic threat" or the development of an elaborate strategy of defence-in-depth, that prompted the construction of the road network in Syria and Arabia and shaped the frontier arrangements that one observes on the ground north and south of the Euphrates. A unique clue to the transformation that he envisaged is provided in the preamble to the Edict on Maximum Prices, issued two years after his decisive defeat of the Persians. The language is unmistakably rhetorical, but there is no reason to doubt that the celebration of tranquillity and 'eternal peace' authentically captured the sentiments of the victorious senior Augustus. It was a peace that only an easterner, by birth and experience, could fully appreciate. The Roman east had been a shambles in 284 - neglected for decades by the emperors, twice subjected to the depredations of Persian armies, and disrupted by the Palmyrene insurrection. The local notables on whom Rome relied had been discredited, the commercial enterprises that made Syria one of the wealthiest provinces had been dislocated, and the garrisons that provided security for the inhabitants had been dispersed or destroyed. For this quintessentially regional Augusts, who visited the west only once after 290, the restoration of the east ws the fundamental task. The preamble to the Edict on Maximum Prices is his proclamation that the task had been successfully completed.