Following the death of Marcus Aurelius, his natural son Commodus was elevated to emperor, and the Roman people shared a hope that the Golden Age would continue. As the first natural son of a sitting emperor since Domitian, Commodus would end up proving the theory that prudent adoption beats genetics.
This is the way Dio described what happened, “Our history now descends from a kingdom of gold to one of iron and rust, as affairs for the Romans of that day.”
From the very beginning Commodus cut an odd figure in his behavior; timid and weak in disposition while becoming a slave to his attendants. These traits caused him to delegate the management of the empire to a series of lieutenants. What followed logically, then, were conspiracies, and shortly after, attempts on his life. In 182 A.D. an assassin employed by Commodus’ sister Lucilla tried to stab him with a dagger and failed. The experience unnerved Commodus and turned him into a paranoid personality. He refused to appear in public and communications with him could only occur through intermediaries. Chiefs of staff rose and fell from power one after the other – most notably Perennis and then Cleander – as their behavior offended the people. Following the death of the latter, Commodus became an unhinged megalomaniac, demanding the Senate deify him and renaming Rome to Colonia Commodiana.
Oddly, it was the palace staff that decided to act against him to save their own lives. The imperial chamberlain, commander of the Praetorian Guard, and Commodus’s favorite concubine plotted his downfall in secret. The concubine, Marcia, poisoned him one evening and when he vomited instead of dying, she engaged a athlete to strangle him. Commodus' body was secretly buried and the Senate informed of his death. The date was New Year's Eve 192 A.D.
The conspirators chose Publius Helvius Pertinax as the new emperor. He was a self-made man who had experienced a meteoric rise from the son of a slave to military commander. Consul in 175 A.D. and governor of Syria in 180, Pertinax won over the Praetorians with a bonus of 12,000 sesterces each. Too idealistic, Pertinax tried to right all of the wrongs of Commodus at once and in doing so alienated all of Rome’s most important constituencies. In early March there was a coup attempted but it was discovered. Then on March 28th, 300 soldiers attacked the emperor’s palace egged on by the Praetorians. Pertinax tried to win over his adversaries with words but they killed him.
Now our story turns to the bizarre. After the assassination of Pertinax, the praetorians returned to their camp and locked the gates. From there they shouted for candidates to come forward and bid for the right to be Caesar. Two men agreed to bid: Titus Flavius Sulpicianus, father of Pertinax’ wife, and Didius Julianus, a rich senator. Didius won the auction because he offered a larger sum and he also convinced the Praetorians that Titus might seek revenge if he were chosen.
This debasing of the Empire caused an immediate reaction among the province commanders. At least three expressed their disgust and declared their intension to assume the position of emperor: Clodius Albinus, governor of Britain, Pescennius Niger, governor of Syria, and Septimius Severus, governor of Upper Pannonia near the middle Danube. Severus had two advantages over the others and they contributed to his eventual success: he was closest to Rome and more aggressive. While Niger dawdled and Albinus was content with a Severus offer of truce, the latter packed up his army and marched to Rome, making the entire 800 mile journey in 40 days. Julianus’ execution was the first order of business after which Severus turned his attention to the Praetorians. He ordered them to muster in a field outside the city walls without weapons. They were surrounded by the Illyrian army with spears pointed at them.
Severus spoke to them and reproached them for their crimes. The Praetorians were stripped of their authority and told to relocate to points no closer to Rome than 100 miles on fear of death. While the speech was being delivered soldiers from Severus’ army took over the Praetorian camp and secured their weapons to prevent any type of countermeasure.
Now with his ascendancy ratified by the assembly, Severus went on a march to destroy his two competitors. By April of 194 A.D. he had defeated and killed Niger. Turning his attention to Albinus, Severus moved west and engaged him in a decisive battle near Lyon on February 19th 197. Albinus committed suicide after his army was defeated.
Severus ruled for eighteen years while the day Didius Julianus purchased the Roman Empire at auction faded from memory.