Bellum desertorum: Commodus versus Maternus

The reign of Emperor Commodus (ruling from 17 March 180 to 31 December 192 CE), son of Marcus Aurelius, began just as the brutal Marcomannic Wars (bellum Germanicum et Sarmaticum) were finally winding down. At its height, according to Marcus Aurelius’s own letters, this conflict involved thirteen legions and dozens of auxiliary cohorts.

The war of 166/167–180 CE may have ended, but Commodus still had to deal with its aftermath, including the banditry that had taken root across regions only recently pulled out of active combat. The most notorious of these bandits was an ex-soldier named Maternus. He was a deserter whose gang grew troublesome enough that Rome eventually declared a full-scale war against them.

Desperation and its consequences

The Marcomannic Wars had badly strained the imperial army, and replacing its losses proved no small task. Fourteen years of brutal military operations and raids had a way of scaring off potential volunteers, so Rome turned to freed slaves (gladiators among them) and brigands (latrones) recruited from the provinces of Dalmatia and Dardania. Many of these new soldiers struggled to adjust to military discipline, pushing back against it in various ways.

Desertion was the most common form of insubordination, and on a scale large enough that even decades later, under emperor Septimius Severus (193–211 CE), Italy, Gaul, and Spain were still being terrorized by armed gangs descended from these same dubious recruits (Birley, A.R., Septimius Severus: The African Emperor).

Maternus, who was he?

The first bandit leader of this kind whose cognomen (the third element of a Roman name, roughly equivalent to a nickname) has come down to us was Maternus. His origins and full name remain unknown, although some scholars (Kajanto, I., Latin Cognomina) argue that the name Maternus — meaning something like “mama’s boy,” “close family ties,” or simply “maternal,” depending on context — points to his Gallic or Iberian origins, since it appeared most frequently among Romanized populations of these two regions. Equally, he may have come from a freedman’s family elsewhere in the empire, where the name also enjoyed some popularity.
Most of what we know about Maternus comes from Herodian’s History of the Roman Empire, itself partly drawn from contemporaries such as Cassius Dio (Roman History), who had been living in Rome as a senator since 180 AD. From them we learn that Maternus was a Roman soldier of unknown unit who, after deserting, built a gang out of fellow deserters, runaway slaves, poor peasants and various fugitives. Why exactly he chose to desert remains a mystery, but he did so while on active duty, taking several other soldiers with him.
Herodian describes Maternus’s earlier “bold” exploits in the army, which had already gotten him into trouble. He seemes to be a soldier with a clear discipline problem, though apparently not one serious enough to warrant severe punishment. Even his desertion wasn’t automatically a death sentence: had he voluntarily returned to his unit (and provided nothing worse like murdering a fellow soldier, perjury, involvement in rebellion, weighed on his conscience) he could have escaped execution.
Roman military law drew a sharp line between ordinary desertion and its gravest form: fleeing to the enemy (transfugae ad hostes), treated as treason (crimen laesae maiestatis).
A soldier who returned to camp of his own accord could hope for his commander’s clemency; one who crossed the empire’s borders and joined its enemies faced death with no right of appeal; death by crucifixion, burning alive, or being thrown into the arena filled with wild beasts.
It’s possible Maternus deserted precisely because he suspected his conduct would eventually catch up with him in a much harsher way, making desertion, and whatever risk came with it, the better bet.

The banditry begins

Maternus and his men main theatre of operations were Gaul, Germania, and Spain, ravaged by them from around 180 CE onward. At first they went after defenseless targets like country estates (villae) and rural communities. Intriguingly, French archaeologists have found traces of destruction in several towns in Normandy and Aquitaine dating to exactly this period (Picard, G.Ch., La révolte de Maternus). It’s possible the deserters even struck larger settlements, including the cities of Limonum and Mediolanum.

The gang’s size grew, possibly into the thousands, earning Maternus the unofficial title of dux latronum, “leader of bandits.” Emboldened, he attacked Argentoratum (modern-day Strasbourg) in the summer of 185 CE. Back then it was a fortified camp of the VIII Legion, Legio Augusta, built on a river island. The attack was repelled, an inscription honoring military tribune Gaius Vesonius Vindex, who took part in defending the fort, survives to this day. The news of the assault however was enough to push the Senate into declaring Maternus and his followers hostes publici: enemies of the Roman state.

The crackdown

Commodus sent a combined force of several legions after the bandits: VIII Augusta, XXII Primigenia, I Minervia, and XXX Ulpia Victrix. Command of the operation in Gaul went to Gaius Pescennius Niger, appointed legatus contra rebelles for the occasion, while additional commanders and auxiliary forces sealed off the surrounding region. Detachments from Legion VII Gemina Felix guarded the Pyrenees along the Gallic-Spanish border, and units drawn from the main force, under Marcus Helvius Clemens Dextrianus, covered Upper Germania.

The main phase of the operation wound down around August 186 CE, when Maternus, recognizing that his band stood no chance, decided to abandon most of his men in Gaul.
The legions hunted most of them down by the following spring, for which they were later on richly rewarded by Commodus himself. Alongside the mopping-up operation came the first trials of captured bandits, who first had to be sorted by citizenship status, the nature of their crimes (army deserters and rural peasants were treated differently), and by whether they’d actually been arrested on solid grounds at all as plenty of arrests, it seems, were made at random.

A farewell bow

Having abandoned most of his men, Maternus and a group of his best soldiers set out for Italy, intending to carry out the act that would earn them a place in the annals of history: the act of killing the emperor.

Avoiding main roads and towns, they eventually reached Rome, where they run into the problem of Praetorian Guard closely guarding Commodus. To improve their odds, they chose the day of Hilaria (25th of March), the festival honoring Cybele and Attis, as the day of their planned assassination. During the procession, celebrants wore masks and costumes, which the conspirators planned to use to get close to the emperor. The plot collapsed on the very day of the festival though, when some of Maternus’s own men betrayed the plan to the authorities. The conspirators were arrested on the spot, and Maternus himself was most likely beheaded shortly after the same day. His men are said to have turned on him out of fear that, once Commodus was dead, Maternus himself would seize the throne, though this explanation doesn’t hold up especially well (for once – Maternus didn’t have any political or military backing).

The final mopping-up operations wrapped up around 188 CE, bringing Maternus’s career to roughly a decade in total, two and a half years of which were spent in open, declared war against Rome.

Aftermath

By Rome’s state propaganda, the war ended in a clean victory: the legions received honorary titles, and Commodus’s image as a defender of the state was reinforced. But it wasn’t the end of banditry, as the later reign of Septimius Severus makes clear.

Grave inscriptions found in what is now France, dated to 194 CE, mourn the deaths of Campanus of New Carthage and Silvanus, both killed by bandits operating in Gaul. In Italy, meanwhile, a man named Bulla Felix emerged around 203 CE. He was Maternus’s spiritual successor, leading a band several hundred strong and plundering the Italian countryside. Modern scholars remain divided on just how serious the banditry problem actually was in this period; some argue the scale of the threat was inflated for propaganda purposes, to magnify the emperor’s successes in fighting it. On the other hand, Commodus’s reign marks the start of a genuinely difficult stretch for Rome, one of mounting social and economic crisis, and the rise in banditry may simply have been an early symptom of that.