Marcus Aurelius: Rome’s reluctant killer

But then something remarkable happened: as if by some divine intervention, a storm broke over the beleaguered legion. Soon, so much rain was tumbling from the skies that the Roman soldiers were able to fill their shields and helmets with water and quench their horses’ thirst.

As for the Quadi, they were assailed by a barrage of hailstones, lightning and thunderbolts. Such was the assault from the heavens on their ranks that some of the Quadi abandoned their own side and went over to join the Romans. The threat to Marcus Aurelius’s trapped legion was averted.

But who or what was responsible for the “rain miracle”, as this dramatic episode in Marcus Aurelius’s 19-year reign as Roman emperor is now known? Cassius Dio says it can be accounted for by the invocations of Arnuphis, an Egyptian magician who had caused Mercury (the god of the air) to send rain to the legion’s aid. Other sources disagree. But whatever the veracity of Dio’s claim, the “rain miracle” offers us a fascinating window into the remarkable life of Marcus Aurelius.

Here was a leader forced to face down a succession of deadly threats from the moment he assumed power in AD 161 to the day he died in AD 180. Unrest on the borders with Parthia in the east, wars on the banks of the Rhine and Danube in the north, a violent uprising headed by one of his governors: all threatened to pitch the empire into chaos. Yet Marcus Aurelius successfully negotiated them all.

Plague, border wars and insurrection all threatened to pitch Marcus Aurelius’s empire into chaos

The irony is that today, 1,900 years after his birth, Marcus Aurelius is relatively little known for his wars. The greater irony still is that, when Marcus Aurelius is recalled in the 21st century, it is chiefly as the first true philosopher-emperor, the man who wrote a collection of personal notes and ideas on Stoic philosophy known as the Meditations. As a result, one of Rome’s prolific warrior-emperors has gone down in history as a man of peace.

Marcus’s interest in philosophy is undeniable. He spent his formative years immersed in study and, as well as developing a keen interest in Stoicism, he was well versed in the works of rival schools, including those of Plato, Aristotle, and Epicurus. How to live the most virtuous life possible while also participating in imperial politics was something he often debated.

But the fact is, the violent two decades in which Marcus ruled left him little choice but to take up the sword. The monumental column erected in Rome shortly after his death emphasises the brutality of the conflicts in which he was embroiled. Marcus Aurelius may not have been a natural-born warrior, but the facts suggest that he was willing to lead his armies from the front – and did so successfully.

Modesty and manliness

Marcus Aurelius was born in Rome in AD 121 to Marcus Annius Verus and the younger Domitia Lucilla. His maternal grandmother, the elder Domitia Lucilla, was extremely wealthy, and the younger Lucilla inherited much of the family’s fortune. Marcus Aurelius’s father could boast of senators and consuls among his ancestors. But for all that, Marcus was not the product of one of Rome’s most prominent lines.

Marcus lost his father at a young age, after which he was adopted by his grandfather, also Marcus Annius Verus. Marcus Aurelius writes about the influence of his relatives in the first book of his Meditations. From his grandfather, he learned “nobility of character and evenness of temper”, and from the reputation of his father he acquired “modesty and manliness”. His mother taught him “piety and generosity, and to abstain not only from doing wrong but even from contemplating such an act; and the simplicity, too, of her way of life, far removed from that of the rich”.

The young Marcus caught the attention of the ruling emperor Hadrian quickly, probably owing to his grandfather’s status. In AD 126, Annius Verus had been appointed consul for the third time, making him the first man to be awarded this honour by Hadrian. When Marcus was six, Hadrian nominated him to be enrolled into the equestrian order, and at seven years old Marcus was enrolled into the priestly college of the Salii by the emperor. Yet the emperor’s patronage of Marcus wasn’t to end there. Not long before his death in AD 138, Hadrian adopted Aurelius Antoninus, the son-in-law of Marcus’s grandfather, as his successor. At the same time, he required Antoninus to adopt Marcus and the young aristocrat Lucius Verus as his own heirs. Marcus’s future now lay on the imperial throne.

When Hadrian died in AD 138, Antoninus became emperor (as Antoninus Pius) and Marcus married the new ruler’s daughter, Faustina. Marcus held his adoptive father in the highest regard, writing in his Meditations that he was gentle, just and modest, “put[ting] a curb on public acclimation and every kind of flattery during his reign”. Antoninus Pius’s reign saw little significant warfare, and the emperor chose to stay close to Rome. The sources suggest that Marcus Aurelius might have been happier presiding over a similar period of imperial peace, but he was not to be so lucky.

In AD 161, Emperor Antoninus Pius died and was succeeded by Marcus and Lucius Verus as joint rulers (Rome’s first co-emperors). That same year, the Parthian king Vologaeses III (or IV) invaded Armenia and installed his own king, Pacorus, in the Roman-protected territory. In response to this act of aggression, the co-emperors reasoned that one of them needed to go to the eastern border in person. They decided upon Lucius Verus, but our two main literary sources diverge on the reasons why. Cassius Dio (who began his political career during the reign of Marcus Aurelius’s son Commodus) suggests that Marcus was too physically weak for military duty, whereas Lucius was 10 years younger and full of vigour. The author of the Historia Augusta (probably writing in the fifth century) says Marcus sent Lucius away to fight because he was worried about his adopted brother’s natural tendency towards vice, and thought that the fear of war would do him good.

If the latter was the case, Marcus’s plan did not go quite as he envisaged, as Lucius lingered in Greece and coastal towns in Asia Minor to enjoy entertainments such as gladiatorial spectacles and hunting. However, once he’d set up headquarters in Antioch, Lucius oversaw a series of victories over the Parthians – and returned to Rome in triumph. For their efforts in putting down the uprising, both emperors were awarded the “civic crown” by the senate (for having saved citizens’ lives) and given the title pater patriae (father of the fatherland).

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Wagons for the dead

The combination of Marcus Aurelius handling matters of politics, law and administration at home and Lucius Verus overseeing military activity on the frontier seems to have worked well against the Parthians. But the jubilation did not last for long. Sometime in the late AD 160s, plague (now known as the Antonine plague) had been introduced to Rome, possibly by troops returning from Mesopotamia. The author of the Historia Augusta describes a scene of chaos and destruction in the city as the “dead were removed in carts and wagons”.

Both emperors remained in the imperial capital for as long as they could to manage the tragedy. Nevertheless, in the spring of AD 168, they set off towards the north, and for a time used Aquileia at the northern tip of the Adriatic as a base from which to go back and forth to the frontier. Then, in early AD 169, calamity struck: Lucius was taken sick in his carriage and died three days later (possibly a victim of plague). Marcus took his dead co-emperor’s body back to Rome for burial. In late summer 169, he headed back to the front as the sole emperor.

Not since the days of Hannibal’s wars with Rome had Italy experienced a foreign army so close to home

Campaigning began again after the winter of 169–70 had passed. The remaining evidence makes it hard to put together a clear narrative of events, but a fourth-century historian, Ammianus Marcellinus, suggests that two more enemy groups, the aforementioned Quadi and the Marcomanni, invaded Italy and laid siege to Aquileia. Not since the days of Hannibal during the wars between Rome and Carthage in the third century BC had Italy experienced a foreign military so close to home. But Marcus Aurelius was up to the challenge.

By late 171, the Romans, now led by Marcus in person, appear to have pushed the invaders far enough back to celebrate a military triumph. Coins were minted in Rome bearing the personification of Victory on the reverse, along with the inscription VIC GER (victory over the Germans, ie the Marcomanni).

Marcus Aurelius remained in Pannonia to receive embassies from the different groups. The Quadi were ready to make peace, and Marcus granted their request in the hope that it would separate them from the Marcomanni. Other groups were granted similar treaties and possibly even settled in Italy, but the Marcomanni in particular remained a potential threat. And so, in AD 172 – the year of the “rain miracle” – Marcus and his army went on the offensive, into the territory on the other side of the Danube. Coins minted in Rome show troops crossing over a bridge.

Marcus’s willingness to negotiate with the Quadi and others was in line with his fair treatment of the enemy, or so Cassius Dio suggests. But even a ruler as apparently even-handed as Marcus Aurelius was moved to rage when the Quadi failed to keep to the terms of their agreement. So furious was Marcus with the backsliding of the Quadi’s new king, Ariogaesus, that he issued an uncharacteristically splenetic outburst “to the effect that anyone who brought him in alive should receive a thousand gold pieces, and anyone who slew him and exhibited his head, 500”.

Sick on campaign

Marcus’s next major challenge came not from an enemy across the Rhine or Danube, but from another Roman. In AD 175, such was Marcus’s successes against the Marcomanni and the Quadi that he was in a position to turn their territory into a new Roman province. But the emperor had to abandon his plans when he heard that the governor of Syria, Avidius Cassius, had rebelled.

The sources suggest that Cassius’s insurrection was prompted by Marcus’s wife, Faustina, because she feared that Marcus had become sick on campaign and was on the point of death (or had possibly already died). Faustina feared that her 13-year-old son, Commodus, was too young to succeed and may have reasoned that it was better for her to remarry before Marcus’s death, so she could protect Commodus from usurpers. The veracity of this story is questioned by the author of the Historia Augusta, who cites letters between Marcus Aurelius and Faustina that vindicate the empress.

While it is difficult to know whether the letters are genuine, it’s certainly common for the female members of imperial families to come under suspicion when ancient historians assign blame for conspiracies. Either way, Cassius was received as emperor in Egypt in May 175. This was a truly perilous development for Marcus, as it was from Egypt that Rome sourced most of its grain supply.

Marcus now summoned Commodus to join him and prepared for a civil war. Cassius Dio then records a speech (which he claims was also sent to the senate) that Marcus delivered to his troops, whom he addresses as his “fellow soldiers”. He expressed regret that so many wars had been conducted during his reign and that civil war had become a threat. He urged the troops that the best course of action, should Cassius be captured, would be “to forgive a man who has wronged one, to remain a friend to one who has transgressed friendship, to continue faithful to one who has broken faith”.

But Marcus was not afforded this opportunity to show mercy. As his soldiers were about to depart, news was brought that Cassius had been killed by a centurion named Antonius. With the help of a cavalry officer, Antonius had stabbed Cassius in the neck, and then cut off his head to present to Marcus. The emperor refused to look at the head and had it buried.

With civil war averted, a significant part of Marcus’s final years was spent back on those same northern borders, protecting his empire from further violent incursions. It was as the campaign season was about to begin in AD 180 that Marcus became seriously ill. He died in March of that year, at the age of 58.

In his Meditations, Marcus stresses the importance of accepting death for what he thinks it is – the decisive end not only of a life, but also of a reputation. “Never cease to observe how evanescent are all things human, and how worthless: today a drop of mucus, and tomorrow a mummy or a pile of ash.” Instead, he counselled, a person must live in the present, paying attention to make sure they lead the best and most virtuous life possible at any given moment.

On a day-to-day basis, Marcus did what he thought he had to do for Rome as its emperor – he managed the administration the best he could, and he steered the troops to and from the front. His focus on present life over enduring reputation perhaps indicates his uneasiness with the violent reality of war. Yet for him, as emperor in the turbulent 160s and 170s AD, conflict was unavoidable. Marcus’s words seek to reassure himself and others that people – even rulers of a mighty empire – can only play the hand they are dealt by divine reason.

Shushma Malik is a lecturer in the School of Humanities at the University of Roehampton

This article first appeared in the June 2021 issue of BBC History Magazine