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Commodus' accession to power, ended a spell of 80 years in Roman history which had brought men to the throne by merit rather than by birth. The last man to take the throne merely by right of birth had been Domitian.
If Commodus merely had not lived up to the gruelingly high standards of his father, the world would have most likely forgiven him. But rather than just failing to be a brilliant emperor, Commodus was in fact a terrible one. Cruelty, vanity, power and fear formed into a terrifyingly dangerous mix of bloodlust, suspicion and megalomania. Commodus should be remembered as a monster, a tyrant who renamed months in his own honour, and who slaughtered his way through the circuses in ludicrous displays of 'manliness'.
Despite his initial promises to the army to continue Marcus Aurelius' attempts of expanding the empire into the territories conquered from the Quadi and Marcomanni, Commodus soon after surrendered all his father had achieved in his wars.
Indeed, Commodus' thoughts that to annex these new territories might have been beyond the capabilities of Rome, could well have been correct. And had emperor Hadrian not relinquished some of the gains of his predecessor Trajan ? But Commodus was no Hadrian and the army knew it. Commodus' retreat from those so direly contested territories was understood as an utter betrayal of everything the beloved Marcus Aurelius had stood for.
Whatever the circumstances surrounding the Roman withdrawal, Commodus did make a treaty with the Marcomanni. The treaty proved very successful in pacifying the barbarians, forcing them to accept various conditions. Although such peace might also have been due to Marcus Aurelius' late successes having reduced the barbarians' capacities for war.
