Ancient Plague Reveals Diverse Origins of Victims in 7th-Century Jordan

A mass grave uncovered in Jerash, Jordan, is offering a chilling glimpse into life during the Plague of Justinian, a devastating pandemic that swept through the Eastern Roman Empire in the 7th century. New research, detailed by NPR, reveals not only the virulence of the disease – Yersinia Pestis, the same bacterium responsible for the Black Death centuries later – but also the surprisingly diverse origins of those who succumbed to it.

The findings, published in the Journal of Archeological Science, stem from analysis of remains discovered in workshops converted into a makeshift burial ground around 650 AD. The speed with which the city repurposed these spaces – ceramic and textile workshops under the Hippodrome – speaks to the overwhelming scale of the crisis. Hundreds of bodies were interred with minimal ceremony, lacking even basic grave goods, a stark indication of the desperate circumstances.

A City on the Trade Route

Jerash, known in antiquity for its pottery and strategic location, thrived as a hub within the Eastern Roman Empire’s trade network. As History Hit explains, the city reached its peak in the 3rd century AD, boasting a population of up to 20,000. However, a series of setbacks – including the destruction of Palmyra, the repurposing of temples under Emperor Justinian, and a significant earthquake in 747 AD – initiated a gradual decline. The plague, arriving in waves after 541 AD, accelerated this process, reducing the population to around 10,000 by the mid-7th century.

The research team, led by University of South Florida geneticist Rays Jiang, employed a combination of mitochondrial DNA sequencing and stable isotope analysis to reconstruct the lives of those buried in the mass grave. This dual approach revealed a surprising truth: the victims weren’t primarily local to Jerash. Instead, they hailed from diverse regions, including central Africa, eastern Europe, and Anatolia. This suggests Jerash, even in its weakened state, continued to attract a transient population – merchants, laborers, and potentially those displaced by conflict or climate change.

A Single Strain, Rapid Spread

What’s particularly striking, according to Jiang, is the genetic homogeneity of the Yersinia Pestis strains found in the remains. “All of the victims we found were killed by a single strain,” he stated, indicating a highly contagious and rapidly spreading pathogen. This finding challenges previous assumptions about the evolution of the plague during this period, suggesting limited mutation occurred as it decimated communities. The speed of transmission, coupled with the lack of effective treatment, meant the disease claimed lives swiftly and mercilessly. Modern antibiotics are effective against the plague if administered promptly, but in the 7th century, there was no defense.

The study also sheds light on the diets and origins of the victims. Isotope analysis of tooth dentine revealed distinct dietary patterns, confirming their diverse geographical backgrounds. Some consumed water from wells, others from cisterns or mountain streams – subtle clues that paint a picture of their lives before the plague took hold. This level of detail is rarely captured in archaeological records, making the Jerash mass grave a uniquely valuable source of information.

Pandemic Response: Then and Now

University of Sydney archaeologist Karen Hendrix, a co-author of the study, notes that the conversion of workshops into a mass grave was a pragmatic, if grim, response to the crisis. The sheer volume of deaths overwhelmed the city’s capacity to provide traditional burials. This echoes patterns observed in other ancient pandemics, as Rutgers University expert Nükhet Varlık points out. After initial waves of plague, cities often relied on influxes of workers to rebuild, inadvertently creating conditions for further outbreaks.

Varlık emphasizes the human cost of these events, reminding us that the victims were not simply statistics but individuals with full lives. “But coming to the same city to die of the same disease,” she said, “It shows us the diversity of how people experience pandemics — which is a universal experience for humanity.”

The Jerash findings also offer a cautionary tale about the vulnerability of mobile populations during pandemics. Those arriving in the city seeking opportunity were likely among the most susceptible to infection, highlighting the social inequalities that exacerbate the impact of disease outbreaks.

Looking Ahead: Understanding Ancient Pathogens

The research at Jerash is part of a broader effort to understand the history of plague and its impact on human societies. By analyzing ancient DNA, scientists can trace the evolution of the pathogen and identify potential vulnerabilities. This knowledge could inform strategies for preventing and responding to future outbreaks. Jiang stresses that while plague has been with humanity for millennia and will likely remain a threat, understanding its dynamics is crucial for effective management.

Further research is planned to investigate the genetic relationships between the Yersinia Pestis strains found in Jerash and those identified in other ancient sites. This could provide a more comprehensive picture of the plague’s spread across the ancient world and its long-term impact on human populations. The site itself, sealed by the earthquake of 659, continues to offer potential for further discoveries, promising to unlock even more secrets about this pivotal moment in history.