Provinces and Principalities under the Early Principate
The end of the Roman civil war after Octavian’s victory at Actium (September of 31 BCE) and the inauguration of the principate (27 BCE) did not herald a substantial change in the political and administrative organization of the Roman Near East. Octavian, now Augustus, continued the policy of client states established by Pompey and pursued by Antony. He did not even change Antony’s clients, except for those in Emesa and Amanus, two states that were briefly annexed in 30 BCE before being given over to client princes in 20 BCE. The Roman province of Syria, enlarged with the Cilician Plain and various peripheral districts to the north (Zeugma, Doliche), became one of the most important provinces in the empire, sheltering three or four legions and encompassing many client principalities (Pliny mentions many of them but adds that there were seventeen more so modest that he felt it useless to list them), while many important client kingdoms were situated around the periphery, notably Commagene, Amanus, Cilicia Trachea, Emesa, Judaea, Abilene, and Nabataea. This did not prevent the province from growing here and there, either definitively (Palmyra most likely between 12 and 17 ce) or temporarily (Judaea-Samaria sometime between the death of Archelaos in 6 ce and the restoration of Herod’s kingdom for Agrippa I in 41 ce; Commagene between 17 and 37 ce).
The details of the evolution of these principalities are not well known, except probably what concerns the various principalities that formed when Herod’s kingdom was carved up. When Herod died (4 BCE), Augustus divided the kingdom between Herod’s three sons, none of whom received the royal title: Archelaos received the ethnarchy of Judaea and Samaria; Antipas received the tetrarchy of the Galilee and Peraea beyond Jordan; and to Philip went the tetrarchy consisting of Gaulanitis, Batanea, Trachonitis, and Auranitis, i.e. a strictly South Syrian state. Starting in 6 ce, Archelaos was destitute and exiled to Vienna (Gaul) for reasons of incompetence and excessive violence. Judaea and Samaria were reattached to the province of Syria and entrusted to the administration of a knight bearing the title of prefect, residing at Caesarea. When Philip died (33–34 ce), his principality was briefly annexed to the province of Syria before being granted, along with the royal title, to his nephew Agrippa I (37 ce), who also received Abila of Lysanias, to the west of Damascus. Antipas in turn claimed the royal title, which prompted his exile in Gaul (39 ce) and the transfer of his states to Agrippa I. Claudius, in 41 ce, rebuilt for Agrippa the totality of Herod’s kingdom, but Agrippa’s premature death in 44 ce prompted the return of his entire domain to the province of Syria. Judaea and Samaria were again entrusted to a specific administrator, now a procurator, while the other sectors were administered directly from Antioch. Nevertheless, Agrippa I’s son, Agrippa II, received in 47–48 ce the principality of his uncle Herod, around Chalcis in Lebanon, and next a part of the Galilee and the whole of southern Syria that had belonged to Philip. Agrippa II kept this territory until around 92 ce, although he does not seem to have died until later, shortly before 100 ce. His main mission was to fight banditry, a task he assigned to the garrisons placed around the Trachon plateau and one that seems to have been carried out with definite success.
The annexation by Rome of the Herodian states around 92 ce fits in with the general policy of integrating client states into the province. Although there had been, outside of Judaea, temporary annexations (such as that of Commagene between 17 and 37–38 ce), or definitely those of smaller states – the Amanus kingdom in 17 ce and Palmyra in c. 12–17 ce), the policy of annexation became more systematic starting with the Flavians. Beginning in 72 ce, Vespasian annexed Commagene and its Cilician Trachaea domains, then the principality of Emesa around 72–75 ce, and that of Arca probably a bit earlier, while the principality of Aristobulus of Chalcis disappeared sometime before 92 ce. The tiny tetrarchs of the Lebanese mountains or the Bargylus uplands further to the north were also destined to disappear during this period: in 115 ce, a descendant of these tetrarchs, Lucius Julius Agrippa, no longer visibly ruled over his ancestral lands and was content to demonstrate his euergetism in Apamea. The annexation of the Nabataean kingdom in 106 ce by Trajan, most likely occurring when Rabbel II died, put an end to the presence of client states to the west of the Euphrates. From then on, Rome administered her possessions by way of three provinces: the original province of Syria with its capital Antioch, governed by an imperial legate of the rank of senator; the province of Judaea, severed from Syria by Vespasian in 68 ce and governed from Caesarea by an imperial legate of praetorian rank until 134 ce, and after that by an imperial legate of consular rank, when it took on the name of Syria-Palaestina; and finally Arabia with its capital Bostra, covering the entire expanse of the Nabataean kingdom from the Hauran all the way to the Hejaz (Hegra marking its southern boundary), entrusted to an imperial legate of praetorian rank.
Roman Expansion across the Euphrates
At the same time as he was putting an end to the vassal principalities to the west of the Euphrates, Trajan was initiating a policy of aggression to the east of the river. On the pretext that the Parthians were intervening in Armenian affairs, which violated the compromise established back in the time of Nero, Trajan launched an expedition against the Parthians in 114 ce, which allowed him to gain the allegiance of various princes on the other side of the river (Abgar VII of Edessa, the Arab dynasts of Upper Mesopotamia, the princes of Hatra), burn the Parthian capital Ctesiphon, and attain the banks of the Persian Gulf where he rekindled a traditional friendship with the king of Characene-Mesene, Attambelos V. He created three new provinces: Assyria, Armenia, and Mesopotamia, and gave a new king to the Parthians, considered henceforth as a client state. One might have hoped to have seen a renewal of the political unity between Syria and Mesopotamia that was typical under the first Seleucids. But uprisings in several Mesopotamian cities and then the death of Trajan convinced his successor Hadrian to abandon the new conquests (118 ce). The three provinces were in effect eliminated, but Rome conserved her friendships beyond the river, and even some supporters. A meeting on the Euphrates between Hadrian and the Parthian king Chosroes I brought the conflict to a definitive close in 123 ce.
When two young princes, Marcus Aurelius and Lucius Verus, rose to the head of the empire in 161 ce, the Parthian king Vologases IV took advantage of the situation and put a Parthian prince on the Armenian throne, which provoked a reaction from the governor of Cappadocia. The Roman retaliation was poorly prepared and ended in disaster and Cappadocia as well as North Syria were invaded by the Parthians. Friendly to Rome, the prince of Edessa, Ma’nu VIII, was pushed out by a rival supported by the Parthians in 162 ce. Leadership of the campaign, decided as soon as the Armenian affair blew up, was entrusted to Lucius Verus who took his time coming to Syria. Not only was Ma’nu reinstated in Edessa, but Rome also annexed a strip of territory along the Euphrates, including the important city of Dura-Europos, which finally became part of the empire in 165 ce; other territories further north, such as Nisibis, were probably acquired during this period. But the Roman army could not pursue its expedition after 165 ce because an epidemic of the plague hit. The prestige that Avidius Cassius, legate of the third legion Gallica and native of Cyrrhus in North Syria, had gained from his victories led him to believe that he could declare himself emperor upon hearing a false report of Marcus Aurelius’s death in 175 ce. Avidius Cassius suffered a defeat almost immediately and was killed.
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