Ancient Pandemics
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I am not a historian of the ancient world so I have no real ability to evaluate these claims, but I wanted to highlight this Bulletin of Atomic Scientists piece by the ancient historian Colin Elliott.
The Pax Romana—the 200-year “golden age” of the Roman Empire—was a marvel of diversity, connectivity, and unchallenged hegemony. By the middle of the second century AD, imperial Rome ruled territory across three different continents. Roughly one-quarter of the Earth’s population, some 60 million people, lived under Rome’s vast aegis, and the emperors of the age—most notably Marcus Aurelius—enjoyed the consent of those they governed. The Empire’s elites—witnessing the disciplined legions, widespread religiosity, cultural efflorescence, and dominant economy—likely expected their world order to endure forever.
In the year 166 AD, however, seemingly eternal Rome was caught completely off-guard as a deadly novel disease swept across the Eurasian landmass. It ransacked Rome’s cities for at least a decade and preceded centuries of decline. This major biological event—now known as the Antonine plague—appears to have been the world’s first pandemic.
Historians hotly debate its death toll—with estimates ranging from 2 percent to 35 percent mortality—and its broader social and economic effects. The disease itself remains undiagnosed. The great Greek physician Galen described its main symptoms as fever, throat ulcers, and a pustular rash. Some have suspected it was measles or smallpox, but modern analysis provides reasons to doubt these as the possible culprits. Human remains from the Antonine plague period, meanwhile, have thus far failed to yield genetic evidence sufficient to identify the pathogen.
Although the plague did not on its own cut short Rome’s dominance, it struck an empire that was confronting multiple challenges beneath a veneer of prosperity and growth—factors that modern-day infectious disease experts might recognize as creating the ideal conditions for pandemics. Much remains unknown about the Antonine plague; in some ways, modern scholars are just as in the dark about this first pandemic as its contemporary victims. But interdisciplinary researchers, trying to understand how the plague could have helped push such a powerful empire to the breaking point, have recently been unravelling some of its mysteries.
Historians, archaeologists, and scientists have been sharing data and expertise, working together to develop histories of past pandemics—including the Antonine plague—that are surprisingly comprehensive and nuanced. Paleogenetic and paleoclimatological evidence reveal the crucial role of environmental and demographic factors in the pandemic. Insights from modern economics and sociology have improved historians’ understanding of how the institutions of the Roman Empire were affected by disease mortality. Even before the pandemic arrived, the pre-existing ecological, economic, and demographic context of mid-second century Eurasia prepared the way for the disease that would accelerate the end of Rome’s era of efflorescence.
Research assessing the severity of modern anthropogenic climate change, for example, has compiled a vast array of climatological data dating back to the Roman period, and well before. Such research offers historians an increasingly detailed and comprehensive view of the ecosystems of ancient Eurasia and Africa. The ancient Mediterranean was (and still is) polka-dotted with microclimates; meanwhile, ice cores from Greenland, ancient tree rings from northern Europe, and sediment cores from Egypt and Italy suggest that some regions in and around Roman territory endured cooler temperatures and droughts about a decade ahead of the Antonine plague pandemic. These climatological shifts were hardly severe, nor did they affect the entire Mediterranean Basin. Many of the affected regions, however, happened to play outsized roles in supplying Roman cities with grain.
The annual Nile flood in Egypt, for instance, reliably nourished well-irrigated grainfields with nutrient-rich water from the Ethiopian highlands. The resulting harvests, often abundant, were stored and then shipped in massive vessels across the Mediterranean to Rome for distribution to the city’s masses. But from the 150s onward, a series of droughts near the Nile headwaters in equatorial east Africa disrupted the flood, reducing the productivity of Rome’s main breadbasket. Meanwhile, at the same time, increased storm activity in the western Mediterranean—as confirmed by sediment cores extracted from the coast of southern France—made shipping already scarce grain far riskier than in previous centuries. As a result, denizens of Rome and several other major cities, and possibly also some of Rome’s soldiers, endured greater food insecurity and malnutrition—weakening their bodies ahead of the pandemic’s arrival in the 160s.