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Late antique plague has never been more contested. Recent scholarship has repeatedly questioned whether the Justinianic plague caused catastrophic mortality and supporters of the traditional narrative of a vast, depopulating sixth-century... more
Late antique plague has never been more contested. Recent scholarship has repeatedly questioned whether the Justinianic plague caused catastrophic mortality and supporters of the traditional narrative of a vast, depopulating sixth-century pandemic have dug in. Scholars have repeatedly assessed evidence thought to prove traditional narratives about the Justinianic plague, but never to everyone's liking. Things have gotten ugly and no resolution is in sight. To advance the debate and shift the focus, these pages review the use of the Black Death in accounts of the Justinianic plague. What follows demonstrates that the claim the sixth-century pandemic killed many millions is founded on centuries of uncritical treatment of late antique sources reinforced in recent generations via the overinterpretation of the first pandemic's plague diagnosis and the neglect of plague's ecological and epidemiological complexities. That the Justinianic plague was another Black Death underpins research agendas and influences the interpretation of data in diverse fields, but it is an unsubstantiated claim, one stemming from deficient interdisciplinarity and neither proven by current evidence nor provable with current methods. Only by strengthening interdisciplinary collaboration, it is proposed in closing, can we begin to remedy our first-pandemic plague problems. KEYWORDS plague, Yersinia pestis, Justinianic plague, disease history, black death, pandemic
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Historians of medicine and disease have yet to think through a syndemic lens. This commentary aims to point out why they should. Although there are several hurdles to overcome, our histories of disease and our understanding of current... more
Historians of medicine and disease have yet to think through a syndemic lens. This commentary aims to point out why they should. Although there are several hurdles to overcome, our histories of disease and our understanding of current syndemics both stand to gain should historians begin to explore episodes of cooccurring diseases that share root causes.
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Smallpox, caused by the variola virus (VARV), is prominent in modern histories of the ancient Mediterranean world. The disease, or the diagnosis of it, has shaped estimations of the scale and significance of epidemics and pandemics,... more
Smallpox, caused by the variola virus (VARV), is prominent in modern histories of the ancient Mediterranean world. The disease, or the diagnosis of it, has shaped estimations of the scale and significance of epidemics and pandemics, notably the 2nd-c. Antonine plague, and the burden of disease in large cities and regions densely populated in antiquity. Here we synthesize recent paleogenetic and evolutionary biological literature that casts significant doubt on the existence of a VARV that caused a disease we would recognizeclinically, ecologically, or epidemiologicallyas smallpox in antiquity. On the basis of current data, it is time archaeologists and historians began to eradicate smallpox from their histories of the ancient world.
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Facing a warming climate, many tropical species-including the arthropod vectors of several infectious diseases-will be displaced to higher latitudes and elevations. These shifts are frequently projected for the future, but rarely... more
Facing a warming climate, many tropical species-including the arthropod vectors of several infectious diseases-will be displaced to higher latitudes and elevations. These shifts are frequently projected for the future, but rarely documented in the present day. Here, we use one of the most comprehensive datasets ever compiled by medical entomologists to track the observed range limits of African malaria mosquito vectors (Anopheles spp.) from 1898 to 2016. Using a simple regression approach, we estimate that these species' ranges gained an average of 6.5 m of elevation per year, and the southern limits of their ranges moved polewards 4.7 km per year. These shifts would be consistent with the local velocity of recent climate change, and might help explain the incursion of malaria transmission into new areas over the past few decades. Confirming that climate change underlies these shifts, and applying similar methods to other disease vectors, are important directions for future research.
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The late antique (ca. mid. 5th century CE) infant and child cemetery at Poggio Gramignano near Lugnano in Teverina (Umbria, Italy) is well-known for its association with malaria. However, less is known about the community members most... more
The late antique (ca. mid. 5th century CE) infant and child cemetery at Poggio Gramignano near Lugnano in Teverina (Umbria, Italy) is well-known for its association with malaria. However, less is known about the community members most closely connected to this cemetery space-in particular, the the infants' mothers. This paper more closely explores the health of the 62 individuals who have been recovered from the cemetery to date with the goal of exploring maternal health status at the time of infant death. Skeletal pathologies are reconsidered within the specific context of the placental fetal environment. Using a biocultural framework and analysis of nested environments, we explore the likely corresponding health of these infants' mothers during late pregnancy and breastfeeding, taking into consideration the wider context of social and cultural factors that mediated Roman women's behaviour, status, and access to resources in rural late antique Umbria. We conclude that these factors, combined with disease stress, profoundly shaped the fertility, morbidity, and mortality of this late antique community. In this context, fetal and perinatal health serve as a useful proxy for community health in the absence of adult remains.
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The influence that meteorological, climatological and environmental factors had on historical disease outbreaks is often speculated upon, but little investigated. Here, we explore potential associations between pandemic disease and... more
The influence that meteorological, climatological and environmental factors had on historical disease outbreaks is often speculated upon, but little investigated. Here, we explore potential associations between pandemic disease and climate over the last 2,500 years in Mediterranean history, focusing on ancient disease outbreaks and the Justinianic plague in particular. We underscore variation in the quality, quantity and interpretation of written evidence and proxy information from natural archives, the comlexity of identifying and disentangling past climatological and environmental drivers, and the need to integrate diverse methodologies to discern past climate-disease linkages and leverage historical experiences to prepare for the rapid expansion of novel pathogenic diseases. Although the difficulties entailed in establishing historical climate-pandemic linkages persist to the present, this is a research area as urgent as it is complex and historical perspectives are desperately needed.
Existing mortality estimates assert that the Justinianic Plague (circa 541 to 750 CE) caused tens of millions of deaths throughout the Mediterranean world and Europe, helping to end antiquity and start the Middle Ages. In this article, we... more
Existing mortality estimates assert that the Justinianic Plague (circa 541 to 750 CE) caused tens of millions of deaths throughout the Mediterranean world and Europe, helping to end antiquity and start the Middle Ages. In this article, we argue that this paradigm does not fit the evidence. We examine a series of independent quantitative and qualitative datasets that are directly or indirectly linked to demographic and economic trends during this two-century period: Written sources, legislation, coinage, papyri, inscriptions, pollen, ancient DNA, and mortuary archaeology. Individually or together, they fail to support the maximalist paradigm: None has a clear independent link to plague outbreaks and none supports maximalist reconstructions of late antique plague. Instead of large-scale, disruptive mortality, when contextualized and examined together, the datasets suggest continuity across the plague period. Although demographic, economic, and political changes continued between the 6th and 8th centuries, the evidence does not support the now commonplace claim that the Justinianic Plague was a primary causal factor of them.

https://www.pnas.org/content/116/51/25546
Recent work has linked historical crises, both regional and local, with palaeoclimatic estimates of global and hemispheric climate change. Such studies tend to underemphasize the spatiotemporal and socioeconomical disparity of human... more
Recent work has linked historical crises, both regional and local, with palaeoclimatic estimates of global and hemispheric climate change. Such studies tend to underemphasize the spatiotemporal and socioeconomical disparity of human suffering and adaptive capacity as well as the complexities of past climate change. We focus herein on the effects in Scotland of a severely cold climate episode in the 1690s, associated with major tropical volcanic events including a large unidentified tropical eruption in 1695. A tree-ring based summer temperature reconstruction from the northern Cairngorms region identifies the 1690s as the coldest decade in Scotland for the last 750 years. Archival sources meanwhile reveal the 1690s as likely the worst era of crop failure, food shortage, and mortality ever documented in Scottish history. The connection appears simple-volcanic cooling triggered famine-but the drivers towards famine are far more complex. Although the unusual coldness of the 1690s was near-hemispheric in scale, it had a differential impact across northwestern Europe. Within Scotland, both lowlands and highlands experienced dire conditions, but distinct factors exacerbated the suffering in each region. We integrate historical and palaeoclimatic records to explore the influence of the volcanic cold pulse of the 1690s and its consequences in Scotland. We find that while cooling temperatures characterized the regional to larger-scale climate, vulnerability and response potential were diverse and shaped by local circumstances. The Scottish crisis of the 1690s, in the context of the kingdom's failing economy, influenced investors from all parts of society, including the nobility and entire communities, to fund the ill-fated expedition to colonize Darien in modern-day Panama. The climate crisis and the colony's collapse hindered Scotland's already sluggish economy, motivating unification with England soon after.
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The Eldgjá lava flood is considered Iceland's largest volcanic eruption of the Common Era. While it is well established that it occurred after the Settlement of Iceland (circa 874 CE), the date of this great event has remained uncertain.... more
The Eldgjá lava flood is considered Iceland's largest volcanic eruption of the Common Era. While it is well established that it occurred after the Settlement of Iceland (circa 874 CE), the date of this great event has remained uncertain. This has hampered investigation of the eruption's impacts, if any, on climate and society. Here, we use high-temporal resolution glaciochemical records from Greenland to show that the eruption began in spring 939 CE and continued, at least episodically, until at least autumn 940 CE. Contemporary chronicles identify the spread of a remarkable haze in 939 CE, and tree ring-based reconstructions reveal pronounced northern hemisphere summer cooling in 940 CE, consistent with the eruption's high yield of sulphur to the atmosphere.
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History and archaeology have a well-established engagement with issues of premodern societal development and the interaction between physical and cultural environments; together, they offer a holistic view that can generate insights into... more
History and archaeology have a well-established engagement with issues of premodern societal development and the interaction between physical and cultural environments; together, they offer a holistic view that can generate insights into the nature of cultural resilience and adaptation, as well as responses to catastrophe. Grasping the challenges that climate change presents and evolving appropriate policies that promote and support mitigation and adaptation requires not only an understanding of the science and the contemporary politics, but also an understanding of the history of the societies affected and in particular of their cultural logic. But whereas archaeologists have developed productive links with the paleosciences, historians have, on the whole, remained muted voices in the debate until recently. Here, we suggest several ways in which a consilience between the historical sciences and the natural sciences, including attention to even distant historical pasts, can deepen contemporary understanding of environmental change and its effects on human societies.
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A symposium on the 1917-19 influenza pandemic, 17 October 2018, Georgetown University.
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An interdisciplinary workshop at Princeton University, 1-3 May 2015.
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Kyle Harper's The Fate of Rome, written for a popular audi
This is the second of a three‐section review of Kyle Harper's The Fate of Rome in which we examine in detail Harper's treatment of two allegedly widespread and mortal Roman outbreaks of disease. In the case of the second‐ century Antonine... more
This is the second of a three‐section review of Kyle Harper's The Fate of Rome in which we examine in detail Harper's treatment of two allegedly widespread and mortal Roman outbreaks of disease. In the case of the second‐ century Antonine plague, we demonstrate that Harper overlooked a major controversy and instead portrayed an oversimplified narrative of a catastrophic event. In the case of the third‐century Cyprianic plague, we call attention to several glaring methodological issues in Harper's treatment of the episode, point out the absence of corresponding evidence in the papyri, and cast doubt on the linkage previously drawn between the plague and archaeology.
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This is the last of a three‐part review of Kyle Harper's The Fate of Rome. Here, we scrutinize Harper's treatment of the Justinianic Plague, demonstrating how he crafts a convincing narrative based on rhetorical flourishes but little... more
This is the last of a three‐part review of Kyle Harper's The Fate of Rome. Here, we scrutinize Harper's treatment of the Justinianic Plague, demonstrating how he crafts a convincing narrative based on rhetorical flourishes but little evidence. We call further attention to several internal contradictions within the chapter and misinterpretations of evidence. We conclude this series of articles with a reflection on Harper's deterministic approach to environmental history. While the environment appears everywhere, agency (people: society and culture) is mostly absent. We finish by emphasizing the need to develop more nuanced causal explanations for complex historical processes and suggest that future attempts to bring together such wide‐ranging material be done within interdisciplinary research teams.
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