Although Commodus had started his reign by putting an end to his father’s war against the Germanic tribes, his own rule was not entirely peaceful. There were skirmishes with the Moors in Africa and with Germanic tribes along the Danube, and according to Cassius Dio the emperor “also had some wars with the barbarians beyond Dacia, in which Albinus and Niger, who later fought against the emperor Severus, won fame.” This conflict across the border of Roman Dacia may have been in 183, and it may have been preceded by an incident the previous year, when a Roman commander allowed some 12.000 Dacians who had been driven from their homes to settle in Roman territory.
A conflict that has been documented only a little bit better, is the war fought against Caledonian tribes in Britannia in 184. In the previous years, the tribesmen had crossed Hadrian’s Wall and had started to pillage the countryside. They had already killed a Roman general and his troops when Commodus became alarmed and sent a capable commander named Ulpius Marcellus to drive the invaders back. Marcellus campaigned against the tribes with great success and pushed them back across Hadrian’s Wall. The general was never popular with the men though, who disliked his strict discipline (a somewhat confused and fragmentary passage in the Epitome of Dio’s Book 73 claims that the soldiers declared one of Marcellus’ lieutenants – the term used is uποστράτηγος – emperor, apparently because they were fed up with their commander’s demands. This lieutenant, one Priscus, refused).
A kingmaker killed
Sextus Tigidius Perennis had been appointed as praetorian prefect in 180 and had swiftly become one of the emperor’s most trusted advisors. Perennis was an Italian and according to Herodianus, he was a capable soldier. The same author claims he was exceptionally greedy and had a bad influence on the young and inexperienced Augustus. His influence on Commodus grew to great heights after Lucilla’s failed conspiracy of 182. Perennis abused his position to get his son appointed as legate of one of the Illyrian provinces, possibly Pannonia Superior, and may have aspired to become emperor himself. This brought about his downfall.
How exactly this happened cannot be established with certainty, as different versions have survived. Dio writes that some 1.500 rebellious soldiers had come to Italy from Britain. They revealed to Commodus that Perennis was aiming to make his son emperor. Thereupon the emperor delivered his prefect to the soldiers, who killed him together with his wife, sister and two sons. Herodianus left us a different and more detailed account. He claims that Perennis had already had coins minted bearing his own image. Soldiers had brought some of these coins to Commodus, who flew into a rage. After rewarding the men, the emperor sent an assassin to Perennis to cut off his head.
He also recalled Perennis’ son from his province and had him executed as well. Perennis had been the sole commander of the praetorian guard. From now on, Commodus would again appoint two praefecti, although this arrangment did not last for long. With Perennis removed, the influence of a freedman named Cleander began to grow. This former slave from Phrygia had managed to become the emperor’s cubicularius (chamberlain). A few years later he would become the sole praetorian prefect.