Europe 166: Lucius Verus’ Parthian War
Lucius Verus traveled to Syria to deal with the Parthian threat in 162, but left the conduct of the war entirely in the hands of his generals. Roman forces retook Armenia the next year then, after a fight over Osroene, invaded the Parthian Empire itself in 165. Despite sacking the capital Ctesiphon and even advancing into Media, the Roman campaign was called off in mid-166 following the outbreak of plague among the legions.
162–165? Chatti–Chauci raids of 162▲
In 162 the Chatti and the Chauci crossed into the Roman Empire, ravaging the Wetterau region of Upper Germania and raiding as far as Raetia. The invasion was apparently defeated by local troops in around 165.
163 Lucius Verus’ Armenian Campaign▲
In the summer of 162 Lucius Verus departed for Antioch to lead the war against Parthia, while his fellow co-emperor Marcus Aurelius stayed on to manage Rome itself. Taking his time on the journey and setting up at a resort on his arrival, Verus largely left the execution of the war to his generals. In 163 two legions under Marcus Statius Priscus drove the Parthians from Armenia, destroying the capital of Artaxata (which they would replace with the newly-built capital of Kainepolis in 164).
163–165 Parthian Occupation of Osroene▲
At about the same time that the Romans were retaking Armenia (163), the Parthians invaded Osroene and deposed King Ma'nu VIII, replacing him with their own candidate. The Romans responded by seizing a number of Osroene cities on the Euphrates, but otherwise spent 163–64 in preparation. In 165 a Roman army under Marcus Claudius Fronto—part of a two-pronged invasion of Parthia itself—entered the kingdom, defeating the Parthians at Edessa and restoring Manu to the throne.
164? Antonine Wall abandoned▲
In around 163 or 164 the Romans pulled back from the Antonine Wall, restoring Hadrian’s Wall to its south as the northern frontier of Roman Britain. Some believe this was evacuation due to unrest fomented by the Damnonii of central Caledonia. To help secure the north, the Votadini, Selgovae, and Novantae—Caledonian tribes who had been under Roman occupation during the Antonine Wall period—appear to have been made Roman clients.
??–Dec 165 Lucius Verus’ Parthian Campaign▲
In 165 two Roman armies under Avidius Cassius and Marcus Claudius Fronto invaded Parthia through the kingdoms of northern Mesopotamia. Defeating the Parthians at Dura-Europos, Cassius advanced to capture and sack both the Parthian capital of Ctesiphon and the great commercial city of Seleucia in December. The Romans then marched to the Persian Gulf, just as Trajan had done half a century earlier.
Dec 165–?? 180? Antonine Plague▲
During the siege of Seleucia in 165, Roman legions became infected with an unknown disease (most likely smallpox), which quickly spread throughout the Empire. Described in some detail by the Greco-Roman physician Galen, the disease claimed approximately five million lives over fifteen years. The army was hardest-hit, severely compromising the capabilities of the Roman legions over the coming years.
166 Lucius Verus’ Median Campaign▲
Following his victory at Ctesiphon, Avidius Cassius attempted to invade the Parthian heartland of Media in 166 but was thwarted, possibly due to the outbreak of plague among his troops. Despite this failure, and despite not leaving Syria during the Parthian War, the Roman co-emperor Lucius Verus assumed the titles of Parthicus and Medicus.
166? Tres Daciae▲
In the 160s the Roman emperor Marcus Aurelius consolidated the three Dacian provinces—Dacia Apulensis, Dacia Malvensis, and Dacia Porolissensis—to form the new province of Tres Daciae (the Three Dacias). This allowed for better coordination of Dacia’s two legions against growing external threats. The three former provinces continued under praesidial procurators, but were now placed under an imperial legate of consular rank, initially Sextus Calpurnius Agricola.