Commodus - Sole Reign (180–192)

Sole Reign (180–192)

Upon his accession Commodus devalued the Roman currency. He reduced the weight of the denarius from 96 per Roman pound to 105 (3.85 grams to 3.35 grams). He also reduced the silver purity from 79% to 76% — the silver weight dropping from 2.57 grams to 2.34 grams. In 186 he further reduced the purity and silver weight to 74% and 2.22 grams respectively, being 108 to the Roman pound. His reduction of the denarius during his rule was the largest since the empire's first devaluation during Nero's reign.

Whereas the reign of Marcus Aurelius had been marked by almost continuous warfare, that of Commodus was comparatively peaceful in the military sense but was marked by political strife and the increasingly arbitrary and capricious behaviour of the emperor himself. In the view of Dio Cassius, a contemporary observer, his accession marked the descent "from a kingdom of gold to one of rust and iron"—a famous comment which has led some historians, notably Edward Gibbon, to take Commodus' reign as the beginning of the decline of the Roman Empire.

Despite his notoriety, and considering the importance of his reign, Commodus' years in power are not well chronicled. The principal surviving literary sources are Dio Cassius (a contemporary and sometimes first-hand observer, but for this reign, only transmitted in fragments and abbreviations), Herodian and the Historia Augusta (untrustworthy for its character as a work of literature rather than history, with elements of fiction embedded within its biographies; in the case of Commodus, it may well be embroidering upon what the author found in reasonably good contemporary sources).

Commodus remained with the Danube armies for only a short time before negotiating a peace treaty with the Danubian tribes. He then returned to Rome and celebrated a triumph for the conclusion of the wars on 22 October 180. Unlike the preceding Emperors Trajan, Hadrian, Antoninus Pius and Marcus Aurelius, he seems to have had little interest in the business of administration and tended throughout his reign to leave the practical running of the state to a succession of favourites, beginning at this time with Saoterus, a freedman from Nicomedia who had become his chamberlain.

Dissatisfaction with this state of affairs would lead to a series of conspiracies and attempted coups, which in turn eventually provoked Commodus to take charge of affairs, which he did in an increasingly dictatorial manner. Nevertheless, though the senatorial order came to hate and fear him, the evidence suggests that he remained popular with the army and the common people for much of his reign, not least because of his lavish shows of largesse (recorded on his coinage) and because he staged and took part in spectacular gladiatorial combats.

One of the ways he paid for his donatives and mass entertainments was to tax the senatorial order, and on many inscriptions, the traditional order of the two nominal powers of the state, the Senate and People (Senatus Populusque Romanus) is provocatively reversed (Populus Senatusque...).