An army in revolt?

Military disorder during the reign of Commodus

One of the many problems plaguing the reign of Emperor Commodus was a supposed “War on Deserters”.

Written by Tilman Moritz on 17 November 2017

“A great civilization is not conquered from without, until it has destroyed itself from within.” These words by William J. Durant close the 1964 blockbuster The Fall of the Roman Empire, but the fall had only just begun. The tyranny of Commodus might have finally come to an end, though there is no turning back from the disorder it caused, a downward spin that will ultimately lead to the fall of the Roman Empire in the West.

In fact, destruction from within seems pretty much the theme of all our sources for the reign of Commodus (r. AD 177–192). A long line of fairly “good” emperors had reached a high point with Marcus Aurelius, the philosopher on the throne, while his son and heir Commodus turned out to be a massive disappointment: he brought the great Marcomannic Wars to an inglorious end by bribing the enemy; he became dependent on unreliable advisors, and; instead of facing up to imminent political and economic crises, Commodus tried to smooth over his weakness by posing publicly as a gladiator.

It is not surprising that Commodus was eventually assassinated.

A “War on Deserters”

One of the great troubles that marked the reign of Commodus, according to the Historia Augusta at least, was the so-called bellum desertorum, the war on deserters. It is explicitly mentioned among the foreboding omina that precede Commodus’ accession to imperial power (HA Comm. 16.1–2).

The very act of desertion is disorder in itself, hence its prominent position there – even if the Historia Augusta don’t advance any further by retelling the full story. Obviously, to Greco-Roman readers there was no need, be it that the story was commonly known, or rather no one should be interested in the hows and whens of such a war, its mere necessity being degrading to any ruler who let it happen.

Source of trouble

In more recent times, historians have tried to reconstruct what really happened there. In 1971, ancient historian Géza Alföldy collected all the evidence for a bellum desertorum he could find – or rather found suitable – in order to unearth an historical course of events. The story he proposed has been criticised and corrected in places, but never challenged in its entirety, despite general and quite serious issues (most of them methodological).

The most glaring mistake is Alföldy’s handling of the Greek writer Herodian (ca. AD 180–240) and his work Tes meta Markon basileias historias, a novel-like history of the Roman Empire since the reign of Marcus Aurelius. Herodian had been one of the main sources for the Historia Augusta (among other Late Roman chronicles), hence Alföldy used him as a starting point as well. Nevertheless, after having assembled his own version from various “historical facts”, Alföldy mocked Herodian for his ignorance of what had been revealed now as the “true story” of the bellum desertorum.

Instead of recounting a “reconstruction” defective in its premises, let us therefore instead look at the source itself.

Maternus the Deserter

The very idea of a deserters’ war was most likely borrowed from Herodian’s narration about a certain Maternus. A former soldier, Maternus fled the army because of (or despite?) his awesome deeds. Taking several comrades with him they soon turned to brigandage and, due to their success, attracted more and more followers.

Some of these followers were hired men, while others were recruited among criminals and prisoners. Herodian tells us that Maternus’ gang gradually grew into what could be regarded as an enemy troop (Herod. 1.10.1). They ravaged the “Celtic and Iberian territories” (1.10.2), so essentially all the north-western provinces, until Emperor Commodus urged his governors on to take counter measures (1.10.3).

A similar story is given in a biography of Pescennius Niger (HA Pesc. Nig. 3.3–5). Alledgedly, he was ordered “to apprehend deserters that back then plagued the provinces of Gaul in countless numbers” (ibid.). Most likely this detail of Niger’s career is fictional. However, it reveals that Herodian’s account was, at some point, taken as factual history, as common ground, something other authors could and did refer to in order to bolster their own story’s credibility.

Even modern historians followed that pattern in that they never challenged the factual accuracy of the whole Maternus storyline. Rather, they were prepared to rewrite it, either by narrowing the event down to places where actual evidence of turmoil could be found or by separating plausible-sounding pieces from supposed exaggerations. The latter is almost exclusively applied to the second act of Maternus’ revolt.

Maternus the Usurper

As soon as Roman authorities began to organise a counter strike but before armies clashed in an actual war, Maternus’ troops disintegrated. In small groups they seeped into Italy, for Maternus, yet undefeated and thirsty for glory, had come up with a scheme as cunning as it was foolhardy: disguised as a Praetorian guardsman he planned to approach the Emperor himself and murder him publicly in order to usurp the imperial purple by force.

However, the somewhat suicidal plot was revealed by some of Maternus’ henchmen, who would rather bear the legitimate rule of Commodus than the despotism of their former ringleader (Herod. 1.10.7). Thus the traitor was betrayed: Maternus was caught and executed on the spot.

As stereotypical or even nonsensical as this part of the story may appear, yet again there is an interesting similarity with another account, this time by the much more respectable Cassius Dio. Although it’s only accessible through a summary preserved in the Epitome (Dio 73.9), the story details an abortive uprising of the Britannic army. Allegedly, in order to avoid persecution the troublemakers sent “emissaries” to Rome who, as it happens, convinced Commodus of their loyalty by accusing Praetorian prefect Perennis of falsehood and ambition to become emperor himself.

Given the considerable number of soldiers involved in this legation – “fifteen hundred javelin men” (ibid.)! – they could just as well be regarded as deserters. Whatever their intentions were – whether or not they had defected to the cause of a usurper before, whether or not they tried to stay loyal to their emperor, or whether or not they were just fed up with being soldiers – their leave was obviously not sanctioned.

Deserted order

It has been suggested that Herodian took a leaf out of Dio’s book on several occasions, and this instance in particular. A common explanation is that he, being a novelist rather than a serious historian, dismantled Dio’s account only to focus on sensational parts or to remodel it entirely.

However, Herodian did not just recycle stories already told. In fact, he chose a deliberately different angle on well-known history. Hence Herodian’s Maternus is neither an undiscerning imitation of Dio’s “robber king” Bulla Felix (Dio 77.10) nor is the whole episode a poor copy of Dio’s elaborate political reasoning. On the contrary, Herodian aims at writing history as a story of individuals. Personality, mental attitude and its development take priority over a factual course of events.

Thus, Maternus’ plot is only one piece of the puzzle to comprehend the motives and actions of Commodus the Man as Commodus the Emperor. In context, the deserter’s attack is the third in a series of four plots leading up to Commodus’ tyranny. First, his sister Lucilla schemed against the Emperor with the aid of some misguided senators. Second, Perennis – the Praetorian prefect and head of administration – and his sons tried to assume imperial power. Third comes Maternus. The fourth blow is delivered by a massive riot in Rome, which results from protests against the corrupt regime of Commodus’ confidant Cleander.

There are some interesting narrative patterns to be discerned here, but suffice it to say that each of these onslaughts is conducted by members of distinct social groups: the senators, the knights, the soldiers and the populace. None of the plotters are actually representative for their class, though: the senators, instigated by Lucilla, don’t act on behalf of the senate nor did the deserter represent the Roman army as a whole.

Nevertheless, this is how Commodus perceives these acts. As a result, the Emperor becomes alienated from each of these groups, which, at the same time, are in general the actual supporters of his legitimate rule. Only after he has lost all of this support, does Commodus resort to autarchy, with a regime based on courtiers, serfs and dependants.

Ultimately, Commodus succumbs to a fifth and final plot as his legitimacy is overruled by his loss of charisma and his loss of credit and credibility with his subjects. In Herodian’s perspective, the disorder that resulted from Commodus’ reign was neither immediately noticeable nor caused by the Emperor’s insanity. Rather, it ori