If you think that choosing a favorite Roman emperor is the most superficial and unnecessary thing imaginable, you would be correct. Great Man history has fallen out of favor in modern historiography, and for good reason. Focusing on an emperor’s life can distract from the broader history of groups and ideas. Yet for much of Roman history, the best sources we have concern themselves exclusively with the lives of the emperors. For me, the lives of the emperors are a chance to indulge in the human drama of history, trying to see from the perspective of the protagonist and setting aside modern concerns about subjectivity and bias. 

No Roman emperor makes a better protagonist than Gallienus, an obscure figure from the third century. Gallienus ascended to the throne in 260, in what was undoubtedly the darkest moment of the Roman empire up to that point. The empire was in the depths of what historians now refer to as the Crisis of the Third Century, but that dry name hardly does justice to the apocalyptic reality in which Gallienus would have lived. The years from 235-285 saw twenty-six emperors appointed by the Senate, the average reign lasting less than two years, as emperor after emperor was betrayed or overthrown by their generals. Mass migrations from central Europe penetrated deep into Gaul and Italy, and rampant inflation brought the economy to a standstill. Plague ravaged the empire’s cities, turning once great metropolises into silent tombs. The empire, and from the perspective of Romans, civilization itself, stood on the brink of collapse. 

Gallienus became sole emperor after his father, Valerian was defeated, captured, and killed by the Persian King Shapur I. Immediately, he faced the largest barbarian invasion in the history of the Roman Empire, as Franks, Alemanni, Marcomanni, Saxons, Goths, Carpi, and Roxolani crossed the Rhine and Danube rivers to raid and settle Roman lands. The sources, likely with some exaggeration, describe the hostile armies as numbering in the hundreds of thousands, but Gallienus rallied the outnumbered Roman armies with astonishing speed, rushing from Gaul to Greece to Italy and back again, defeating the invaders in a series of brilliant victories. 

Yet the invaders Gallienus faced were nothing compared to his domestic threats. During his eight-year reign, Gallienus faced at least half a dozen attempted usurpers, although some sources put the number as high as thirty. Generals proclaimed themselves emperor across the whole empire, from Britannia and Hispania to Gaul, Egypt, and Palestine. Two of Gallienus’ sons were murdered by treacherous subordinates. Yet Gallienus acquitted himself well, defeating numerous usurpers in battle as he struggled to hold back the unstoppable forces of chaos. 

As he rushed from one crisis to another, Gallienus somehow found the time to reform the Roman army, abolishing an outdated system of nepotism in favor of meritocracy. He established an elite all-cavalry strike force in his capital of Milan, to deal with sudden threats. 

But in the end, even Gallienus could not hold the empire together. Two prominent Romans in the east and west declared themselves emperor, splitting the Roman empire into three. Before Gallienus could respond, his right-hand man, the general Aureolus, betrayed him, seizing Milan. As Gallienus lay siege to his own capital, he might have felt that all his work had come to naught. One night in 268, woken by news of an attack by the besieged Aureolus, Gallienus was murdered by a group of his own generals. 

The main source we have about the life of Gallienus, the Historia Augusta, is deeply critical of the emperor, accusing him of avarice, lust, and cruelty. However, modern historians consider the Historia Augusta a partisan and often wildly inaccurate source. We know that Gallienus spared the lives of at least one of his treacherous generals, and that he permitted the defeated Alemanni to settle within the empire. The sources make it clear that Gallienus was far from a bloodthirsty warlord. Even as he fought to defend the empire, Gallienus won renown as a poet and orator in the classic Greek style. During the few moments of respite during his reign, he helped to sponsor an artistic reawakening in Rome, leading to a notable uptick in art and philosophical writings in the capital. 

Historians typically give much of the credit for ending the crisis of the third century to the emperor’s Aurelian and Diocletian, the former who reunited the empire and the latter who finally stabilized it. Yet it is hard to imagine that there would have been an empire to salvage had not Gallienus fought so hard to preserve what he could. As historian Michael Grant has written “the fact that the Roman Empire did not fall apart in the 260s or 270s A.D. is one of the great miracles of history.” Aurelian (who, incidentally, was one of the generals who betrayed and murdered Gallienus) based his successes on the military which Gallienus had painstakingly rebuilt. 

No emperor ever worked harder against longer odds to preserve the Roman Empire, and few showed greater ability than Gallienus. Gallienus was dealt a losing hand, and he played it far better than most, certainly vastly better than the succession of mediocrities who had preceded him. Yet despite his effort and ability, few would have called Gallienus’ reign a success. To me, Gallienus represents an individual’s struggle against destiny. To the reader of history, there is something miraculous, almost preordained about the fantastic successes of Aurelian and Diocletian. In the story of Gallienus, we see a protagonist with all the ingredients for success except good fortune. I read Gallienus as a tragic hero, a reminder that the tides of history sweep away great men as well as mediocre ones.