Parthian-Roman Wars

Founded and ruled by the Arsacid royal family, the Parthian empire (c. 250 bce–227 ce) was the native Iranian empire that filled the power vacuum in the Middle East in the midst of Seleucid decline. Arsacid interaction with the Roman empire began in the mid-90s bce, eventually established the Euphrates river as a shared border, and was peaceful in nature till 54 bce. In that year, the first of four cycles of Parthian-Roman wars began. Since the Romans carried out the initial large-scale mobilization of troops that introduced most of these wars, it is appropriate to associate these four cycles with the various Romans who coordinated the Roman military efforts: (a) Crassus to Antony (54–30 bce); (b) Nero (57–63 ce); (c) Trajan (114–117 ce); and (d) Lucius Verus to Macrinus (161–217 ce). The fundamental causes for these conflicts were Roman imperialism, which was well ingrained by the 1st century bce, and Parthian imperialism, which accelerated in the 2nd century bce, probably accompanied by the Arsacids’ attempts to present themselves as successors to the Achaemenid dynasty. These traditions led the Romans and Parthians to expand their spheres of power such that they came to meet in Armenia and Mesopotamia, over which regions they fought at different points for the three-century period of their empires’ coexistence. Even so, Rome and Parthia enjoyed lengthy periods of peace. Conflict was neither inevitable nor constant. In many cases (particularly in the late 1st century bce and 1st century ce), Romans and Parthians alike preferred peace and succeeded in maintaining it; but they presented diplomatic negotiations and limited military actions in ways that proclaimed hostility and martial victory (real and imagined). In this way, however, the persistent image of conflict conditioned the Roman people, especially, to accept and even expect such war. This aggressive anti-Parthian rhetoric, for example, enabled Emperor Trajan to break with years of peace and invade Mesopotamia (114–117 ce). In this way, the image of Parthian-Roman war was made a reality.