New Questions for Studying Plague in Ottoman History
Plague is an infectious disease caused by the bacterium Yersinia pestis. It is known to have affected human societies for at least the last five thousand years. During its long history, it sparked countless local epidemics and three known pandemics, which spread the bacterium to practically every corner of the world. (Today, plague exists in all the continents, except for Antarctica and Australia.) Hence plague is not an extinct disease. Quite the contrary, it is well and alive, especially in some parts of the world (e.g., the southwestern United States, Central Asia, and Africa), where it is enzootic (i.e., present in animal populations—mainly rodents). In those areas where an active plague reservoir still exists (see Map 1), the disease can occasionally spill over into human populations to cause sporadic cases and less frequently result in epidemics.
Plague is still one of the most lethal infections in the world today, though it can be treated with antibiotics. No longer a major public health threat, plague offers unique perspectives into the study of infectious diseases. The exceptionally slow evolution of the plague bacterium (Y. pestis) can shed lights onto the deep history of disease pathogens and their dynamic relationship with human societies across the ages, which makes plague a model infection to study. Plague also lends itself well to new approaches in molecular archeology and paleogenetics, and is at the forefront of ancient DNA (aDNA) studies. It is no wonder why plague studies is a truly multidisciplinary and diverse field; it is only fitting that a field of study that examines an ancient (but still ongoing) disease requires the expertise drawn from disciplines as diverse as history, archeology, paleogenetics, and ecology across the humanities, social sciences, and the natural sciences.
In the study of long and global history of this disease, Ottoman history has something quite unique to offer. The Ottoman experience of plague is the longest continuous manifestation of this disease in recorded human history: from 1347 to 1947—six hundred years of plague. It thus presents an exceptional chapter in the history of this disease. What makes the Ottoman experience even more intriguing is the empire’s tenacious record-keeping bureaucracy that left behind an extraordinary body of documentation to track recurrent plague epidemics in this part of the world over six hundred years.
Despite this rich body of evidence that can lead to new perspectives in the history of plague, the Ottomanist scholarship in this area has been slow to develop. And while the Ottoman experience of plague has been the subject of scholarly studies and can be approached from multiple angles, such as the natural history of the disease, its circulation, mortality, economic impact, cultural impact/production of knowledge, biological and cultural legacy, there remains much to be explored. One of these is the question of plague’s persistence. How did this disease remain active in Ottoman society for no less than full six centuries? Plague’s long history in Ottoman areas can hardly be explained by re-introductions of the infection each time from outside, which makes it imperative to study the mechanisms of plague’s persistence in the region. How did imperial structures, human and non-human mobility, and urbanization perpetuate the infection? Were there any particular set of circumstances in the empire’s vast landscape that help sustain it? Research coming out of paleogenetics and ecology point out that plague persistence is a complex phenomenon, and while we can seek some answers to these questions, the present state of research is not adequate to answer them with confidence. In what follows, I offer some suggestions about possible avenues to explore the persistence of plague in Ottoman history.
In recent years, a growing number of scholars started paying closer attention to plague’s persistence. Studies that examine both active and extinct reservoirs suggest that its persistence is governed by complex social, epidemiological, and ecological processes. The study of past reservoirs in particular requires shifting the gaze away from human-centric perspectives toward dynamic multi-protagonist models. The epidemiological fluctuations of the disease can be best studied in conjunction with the changes in plague reservoirs. How do such reservoirs expand or contract over time? What are the larger climatic, environmental, and human-induced changes that affect them? How do rodent colonies respond to such outside changes and how does this affect their ability to keep the infection alive and pass it on to humans?
There is now a growing, albeit controversial, body of evidence about the environmental mechanisms that sustained the infection historically. On the basis of paleogenetics evidence, there is a newly emerging consensus about a single introduction of the infection to Europe (and probably to the larger Mediterranean world) during the Black Death and its persistence thereafter. Given the limited number of available aDNA samples (especially outside of Europe), this consensus begs for more careful and historically-grounded explanations about the social, epidemiological, and environmental conditions that made long-term persistence possible.
Historical Plague Reservoirs in Ottoman Anatolia
Ottoman Anatolia can offer a fascinating case to study the empire’s once active plague reservoirs. To clarify: there is no evidence that the bacterium is still present in Anatolia and its surroundings today, though that would require a specific kind of research looking for evidence of Y. pestis in wildlife. What we can say instead, there are no recorded cases of human infection of plague in Turkey and its neighboring countries in recent decades. The last cluster of human cases in the region was in 1947 in a small village in Akçakale (Şanlıurfa) and its surroundings on the Syrian border.
Even though we do not currently have Y. pestis aDNA from Anatolia, there is no question that plague survived in the region, causing countless outbreaks possibly since the Bronze Age. Plague reservoirs of Ottoman Anatolia were presumably seeded by the branch of the bacterium that was introduced to the Mediterranean world during the mid-fourteenth-century Black Death, or possibly earlier. If plague finds a favorable natural environment among ground-burrowing wild rodents, it forms a niche to sustain itself from one season to the next. Given the typical behavior of the disease and the conduciveness of the Mediterranean environment to its dissemination and persistence, plague likely established Anatolian reservoirs soon after its initial introduction in the late medieval era. These reservoirs likely became the main engine driving plague’s persistence in the natural environment and thus responsible for spilling over to infect commensal rodents (mainly rats) and humans.
Ottoman Anatolia has diverse microclimates and microecologies, ranging from the coastal strips in its western and southern shores (with warm Mediterranean climate; cool, rainy winters; hot and moderately dry summers) to their immediate hinterland of semi-arid zone, and from the Black Sea coast with temperate oceanic climate (wet and humid; cooler, more precipitation; eastern part receiving rainfall year around) to the interiors of the peninsula with continental climate and low rainfall. Moreover, a critical component of Anatolia’s ecological diversity is elevation. For example, the Taurus mountain system that divides the Mediterranean littoral from its hinterland is considered to be part of the Alpine-Himalayan belt of Eurasia, stretching from the Himalayas to the Atlantic including the Alps and the Pyrenees. This mountain system and its surrounding basins contributed to Anatolia’s complex topography and nurtured a rich biodiversity especially in the pre-modern era. Given its diverse ecological conditions conducive to sustaining plague, Anatolia likely housed a conglomerate of plague hotspots (micro-foci) of various size, longevity, and level of activity, but out current knowledge does not allow us to identify their location.
Research from the Italian Alps and other regions of the Himalayan belt, as well as from Madagascar point out to the highlands as possible plague reservoirs. Given Anatolia’s rich mountain ranges that housed an abundant diversity of flora and fauna, they likely housed plague reservoirs. The southern hills of the Taurus mountain range facing the Mediterranean and the northern hills facing the Black Sea seem to be ideal cases to study for their potential to harbor such reservoirs. The plateaus of central Anatolia with its steppe-like landscape also likely supported plague reservoirs. Even though we do not yet have the zooarchaeological evidence to prove the historical presence of rodent reservoirs, those are areas that need to be explored more closely for their potential to house the infection in the wildlife.
Identifying where the reservoirs were located and how they functioned is the main question, but there are other critical questions that need to be explored to better understand the ecology of plague in Anatolia. Such an effort involves identifying the wild rodent species that once hosted the infection, as well as their historical patterns of distribution. Only then will it become possible to propose hypotheses regarding how they may have interacted with the fauna and how the infection may have spilled over to humans. In the case of Anatolia, the role of pastoral nomads inhabiting Anatolian highlands seasonally and their movements between the highlands and the lowlands would require close scrutiny, as the infection would have been carried either by humans or animals (or their ectoparasites) or via goods like leather, hides, textiles that the pastoral nomads supplied for Anatolian towns. The network of roads that connected Anatolia’s ecologically diverse areas to one another would also need to be examined with respect to its role in facilitating the dissemination of the disease. Moreover, studying the long-term persistence of plague in Anatolia would need to interrogate the multiple ways in which different members of Ottoman society interacted with nature, managed natural resources, and were in turn affected by the ecological consequences of their policies and interventions. Addressing these questions would also likely lead to answers to understand why the plague reservoirs eventually declined and the disease disappeared from the region over the course of the nineteenth and twentieth centuries.
Nükhet Varlık is Associate Professor of History at the University of South Carolina and Rutgers University–Newark. She is a historian of the Ottoman Empire interested in disease, medicine, and public health. She is the author of Plague and Empire in the Early Modern Mediterranean World: The Ottoman Experience, 1347–1600 (2015) and editor of Plague and Contagion in the Islamic Mediterranean (2017). Her new book project, “Empire, Ecology, and Plague: Rethinking the Second Pandemic (ca.1340s-ca.1940s),” examines the six-hundred-year Ottoman plague experience in a global ecological context. In conjunction with this research, she is involved in developing the Black Death Digital Archive and contributing to multidisciplinary research projects that incorporate perspectives from palaeogenetics (ancient DNA research in particular), bioarchaeology, disease ecology, and climate science into historical inquiry. She is the Editor of the Journal of the Ottoman and Turkish Studies Association (JOTSA).
First publication of this text in: TRAFO – Blog for Transregional Research, 29.06.2021, https://trafo.hypotheses.org/29284.