Throughout ancient history rapacious diseases have repeatedly devastated populations-in many cases proving that bacteria and viruses are far more of a threat than human violence or malfeasance.  But the human response to pandemics evolved, as we learned, sometimes in small ways, sometimes large, how to protect ourselves better. Even in the Medieval European world, the battle against the plague was not hopeless, and after the Black Death’s initial and brutal assault (1348-50) its aftershocks–follow-up outbreaks—were milder, partly  because people were more resistant, but more likely because of social and political action on the part of affected communities. This accommodation of the plague was pivotal in the development of government in the medieval/early modern world,  for better or worse, since public health entailed greater control and surveillance over populations.

In addition to the growth of government as a consequence of plague, this story can also be seen as one of a scientific method emerging through the mist of history as people used observation to modulate behavior in respect to disease. Whereas, in Europe at least, initial responses to plague were generally hysterical, they soon eased somewhat as people started paying closer attention to the phenomenon–and drawing conclusions. This paid dividends, and responses to subsequent outbreaks of plagues were far more measured, and useful.

Historians have traditionally described three pandemics of what has generically been referred to as “plague” in history. The first, in 546 c.e. was known as the Plague of Justinian, after the Byzantine emperor, ruling from Constantinople. Though that city was hit hard, plague also bedeviled large parts of the Mediterranean and North Africa.   The second was the  plague of 1348-50, and the several years following. Whilst best documented in Europe, this pandemic covered all of Eurasia (the Americas having not been “discovered” yet, had to wait for the arrival of Columbus before they received their first dose of Old World diseases). The third occurred in China and India between 1894 and 1922, and while still meriting the term “pandemic” it did not have the killing power of the medieval plague.

Having said this, these three outbreaks were merely “ground zero” in terms of dates. Plague outbreaks lingered for decades afterwards, like tremors following an earthquake, but they were generally of much less significance. After the outbreak of the sixth century for example, there were others, notably in England and Italy in the eighth century and again in the seventeenth in various parts of Europe.

Whereas the ancient or medieval victims of plagues had little explanation other than  the old he-moves-in-mysterious-ways line, we now have pretty solid–if incomplete–explanations. Notwithstanding these progressive developments, the fact remains that the plague is still active in North America, and still kills a small number (6 or 7 people) every year, residing in the animal reservoirs of, particularly, prairie dogs, mostly in western states.

My point today, though, is to look at the ways in which plague experience has changed historically, given the fact that plague has not been eradicated. Such change is very possibly one of the main arguments for “progress” in human history, which is a debate I will be dwelling on from time to time here. Plague has not disappeared from the world, and one of the biggest questions historians and more importantly epidemiologists ask is why it goes away from time to time, not just why it pops up from time to time. To what extent have we adapted to plague so as to minimize its effect?

The last pandemic occurred in India and China between 1894 and 1922, and was responsible for killing some 12 million people. Europe’s last real experience of plague was in Messina in Sicily in 1743. I say “experience”  here because unlike the Black Death, this 1743 event  had a weak showing. Since then the plague has more or less disappeared from Europe.

The ancient world saw many epidemics, but we can’t know exactly what these were. Even the nature  of the “Black Death” of 1348 is still subject to controversy, recent scholars suggesting it was not in fact Yersinia Pestis, the bacterial infection carried on rats, but a viral infection, more like Ebola. This would account for its rapid spread and the success of some communities in stalling it by quarantine–something you can’t do with a rat-borne disease. The Athenian Plague, for example, which erupted during the Peloponnesian War of the 3rd century BCE, could have been smallpox, bubonic plague, measles, or even anthrax, unearthed by the footfalls of thousands of refuges and the overcrowding of humans with animals. Several hundred years later, in Rome’s heyday, pestilence tore through its armies; in 165 c.e,  its war machine was decimated by disease on campaign in Syria. In the capital itself, in the mid-second century CE, some 5000 people were dying each day over several decades from a disease that could have been bubonic plague or possibly smallpox. Similarly in China, at about the same period, plague of some kind was rife among soldiers fighting the dreaded “barbarians” in the northwest.

As to what caused these pan-and-epi-demics, plague watchers tend to avoid  one-cause explanations. Instead, in most instances various and perfect storms of causes coalesced. But one contributor to these pestilences seems to have been the climate.  In the second century, for example, the global climate was cooling. The Roman Warm Period which had preceded it had enabled Roman expansion, guaranteeing good harvests–and wealth– as it had in China, and therefore population had burgeoned. But with all booms there must be a bust. Growing populations came with built-in control systems. With more people came more commerce and with commerce came contact, the petrie dish of plague. In the case of the Roman and Han empires of the first century c.e., the embryonic “Silk Road” (in quotes because it was really a network of routes) connected everything from China to the Mediterranean, and along with the exchange of silk, precious metals and leather, there was also microbial exchange.

Several centuries later, at the time of Justinian, the Byzantine emperor of the sixth century, millions of people died of plague in and around Constantinople, and in communities all to the way to Egypt. Even Justinian caught the disease–but recovered. This one is believed to have come with rats (rattus rattus, the Black rat), which carried fleas, which were the final transmitters of disease. The rats followed the grain which came into Constantinople as tribute mainly from Egypt, which the historian Procopius  identified as the origin of this particular plague. This one, he said, was “a pestilence by which the whole human race came near to being annihilated.” Everything ground to a halt. “In a city overflowing with good things a harsh famine ran riot. It seemed hard and indeed very remarkable to have enough bread or anything else.”

Reports from contemporaries may have been exaggerated–images of corpses piled up on the streets, rotting. But apart from a possible tendency for ancient historians to exaggerate, and to copy the descriptions from other ancient accounts of other plagues (these descriptive elements therefore being kind of memes–heaps of corpses, entire villages emptied, grave yards overflowing, etc), the descriptions we have are often entirely believable also; many commentators report eerie silences in the city as entire households were emptied of the living. Many others fled, often against the orders of religious authorities (there is no fleeing from God’s wrath, as Pope Gregory pointed out, rather pessimistically, during an eighth century outbreak). Nonetheless many followed the Roman physician Galen’s more helpful if not very medical advice from his experience of  ancient plagues: “Flee fast, far, and for a long time.”

Citizens of both Constantinople and Alexandria were reluctant, however, to leave their homes without name tags; in case of sudden death, their bodies could be brought home, although most reports are of unmarked, mass graves, there not being enough hands to bury all the dead.

But the pandemic we are most familiar with was the Black Death of the 1340’s and 50s.  Having long since recovered from the plague of the sixth century, the medieval population of Eurasia was on an upswing. Trade and contact between east and west was growing again. The Silk Road was buzzing with merchants, priests, soldiers. This pandemic was to be huge. According to the Foster Scale, devised by a Canadian geographer to measure worldwide calamities, the Black Death was the second worst thing to ever happen to humanity. The first was World War Two. The third was World War One.  The US Atomic Agency considers the Plague to have been closer than any event in history to the destructive power of a nuclear war. These perspectives look at the plague from the point of view of death toll and its wider consequences. Europe was hit hard, especially over two distinct years, 1348-50, but the rest of Eurasia was hammered too, for years. “In a handful of decades,” writes historian John Kelley,”Yersinia Pestis swallowed Eurasia the way a snake swallows a rabbit–whole, virtually in  a single sitting.”

Estimates of mortality are hard to pin down, but globally more than 60 million people are thought to have died. In Europe where the best estimates exist, some 40-60 percent of the population succumbed, with eastern England and rural France being severely affected. Elsewhere was no picnic either. “It was as if,” wrote Ibn Khaldoun from the Middle East, “the voice of existence had called out for oblivion.” The world was massively depopulated, an experience that it is hard to imagine. The Italian poet Francesco Petrarch wrote, “once we were all together. Now we are quite alone. We should make new friends, but where, or with whom, when the human race is nearly extinct, and it is predicted that the end of the world is soon at hand?”

Where did it start?

No  one knows for sure. Possibly along the Volga.  Or on the shores of the Caspian Sea. Or perhaps in Kyrgyzstan. A simple headstone on a grave here reads, “In the year of the Hare (1339). This is the grave of Kutluck. He died of plague with his wife Magna Kelka.” This could have been victim 1, on a mountainside near lake Issyk Kul, which, one can only imagine, was even more desolate than it is today.  It’s impossible to know how events played out at this homestead. But one of them, Magna Kelka or Kutluk, let’s say it was the wife, would have become sick first. Coughing ensues; she begins bringing up blood. Pustules appear on her skin. There is no recourse, here, no medical facilities, and no one on earth at this point in history has the faintest idea what this disease is, or how to treat it. Prayer is the only remedy, as God must have been the only origin and explanation (mysterious ways, etc.). But prayer didn’t work. Both husband and wife went to their graves not knowing what was happening, much less why, but probably understanding where it was to end.

(The most accepted theory of transmission–and of the Plague’s identity–is that it was Yersinia Pestis, the bacterial infection, although as I mentioned above this is not universally accepted. Here, however, I will outline the argument for it and its transmission).

Whether or not it was sent by God, the plague began its life on earth with an obese kind of  marmot, to be precise a Tarbagon. This creature’s habitat was usually sufficiently out of range of humans, but with the increase in traffic along Inner Asian trade routes in the fourteenth century, connecting the eastern and western cores of China and the Mediterranean, the space between human and tarbagon shrank.  To make matters worse, in the fourteenth century the global climate was cooling, and this would have pushed the tarbagon south, out of their habitat and closer to the trade routes which themselves were becoming ever-busier. In  addition, the nomadic herdsmen of the Gobi desert were experiencing drier conditions and migrating further into tarbagon territory. Here the fleas that travelled with the tarbagon hopped onto the rats which travelled with humans, rats being a species commensal with humans.

Once in range of humans, the plague found a geo-political context that made Yersina Pestis‘ travels easier: for this we can blame the Mongols. In the late thirteenth century, under Genghis Khan, these warrior nomads had burst out of the steppes to conquer large swathes of Eurasia. In fact they created the largest contiguous empire in history in the course of a generation. This was very nice–if you were a Mongol–and this new life of military aristocrats certainly beat eking a meagre existence out of the steppe by stealing your neighbor’s horses and daughters (and wives and mothers, come to think about it). And for those non-Mongols who survived the conquests, it had its upside too.  Having stitched together the world’s largest free-trade zone, merchants now used the ancient trade routes in ever greater numbers, going further than ever before without encountering borders.  Such ease of transportation meant that the disease was now likely to go far.

While the cooling temperatures put humans and tarbagon together, they also tended to damage the human immune system. As hunger became a problem among many communities experiencing failed harvests, human resistance to disease faltered just at the wrong time.

The likelihood and frequency of war and violent conflict meanwhile increased everywhere, as the various horsemen of the apocalypse gathered to strike their blows. This spiraling into violence was particularly acute in the hardest-hit European venues such as England and France which were busy destroying each other in knightly combat. Most of this combat happened on French soil, during the Hundred Years’ War (1337-1453). When French feudal lords barricaded themselves in their castles instead of sallying forth to fight, the English took to burning surrounding fields and destroying villages.  Hunger and homelessness was rife in France (as it was in England in the decades leading up to the Black Death because of failed harvests).

European population in 700 was about 26 million. By 1200 it had tripled to 75 million. The Great Clearances of the twelfth and thirteenth centuries created all the farmland for the bigger population. But as environmental historian Donald Hughes says, “As the human population was being clothed, the land was being unclothed.” Trees were cut, sheep introduced to pasture, soil erosion began in earnest. And farmland suffered, becoming exhausted. People herded themselves into European cities, which ballooned. Paris had a population of 100,000 in 1300. These cities were among the filthiest on the planet, owing partly to Christian attitudes to personal hygiene (at this time cleanliness was vanity, not “next to godliness”).  A surprising number of street names in Paris are derived from the word merde (shit);  rue merdeux,  rue merdelet, rue des merlons.  From Shitty Street, to the Road of Little Turds, as John Kelley says: ” ‘Look out below’ was the only sanitary ordinance.”

A succession of wet summers culminated in the Great Famine of 1316. This was bad news for children, who would be in their thirties when the Black Death hit; the results of malnutrition would have permanently weakened their immune systems.

As famine struck Europe in the early 1300s, plague started consuming the East.  Fleas on the trade routes migrated from tarbagon to rats, then hopped rides with them from caravanserai in the Gobi desert. They surfed the Silk Road from China to Baghdad.  By the 1330s plague had appeared in the middle Yangtze valley in China. It reportedly killed 9 out of 10 people, a ninety percent mortality rate. Half of the entire province of Hopei, some five million people, died in 1334.

It continued to ravage different parts of China for several years, while  also moving west. Different theories about the Plague’s route into in Europe exist. But perhaps the most arresting is the story of Caffa and the Genoese merchants.  In 1347 the Black Sea port of Caffa (today’s Feodosiya) was under the nominal control of the Italian merchant city of Genoa. The Genoese had an agreement with the Mongols to use the town as a trading entrepôt. Arguing with the Mongols (not clever) about the terms of use, the Genoese were faced with a Mongol onslaught. As the Mongols readied themselves to unleash their usual death and mayhem upon the Genoese in the city, they began to sicken. Always ones to improvise, the Mongols  started (according to several possibly spurious reports) to lob diseased bodies over the city walls into Caffa–this is sometimes touted as the first recorded incidence of biological warfare. Not that the germ theory of disease was known to the Mongols, but they must have noted that it was spreading, somehow, and put two and two together. Even the Mongols had an embryonic notion of scientific methodology, beginning with keen observation. Other historians more soberly argue that before the bodies came over the walls, the rats would have tunneled beneath them and would have constituted a fast-moving unseen wave of pestilence.

As people within the city succumbed, panic broke out in the streets. “As the death toll mounted,” says John Kelley, “the streets would have filled with feral animals feeding on human remains, drunken soldiers looting and raping, old women, dragging corpses through rubble, and burning buildings spewing jets of flame….” And in the harbor from which the only escape was possible: “surging crowds and sword-wielding guards, children wailing for lost or dead parents, shouting and cursing, everyone pushing toward teeming ships.”

Some ships did make it out amid this chaos, and this is possibly what sealed Europe’s fate. According to the Italian chronicler Michele de Piazza: “It so happened that in the month of October in the year of our lord 1347, around the first of that month, twelve Genoese galleys, fleeing our Lord’s wrath [again, the only explanation that computed] which came down upon them for their misdeeds, put in at the port of Messina [in Sicily]. They brought with them a plague that they carried down to the very marrow of their bones, so that if anyone so much as spoke to them, he was infected with a mortal sickness which brought on immediate death that he could in no way avoid.”

Needless to say the Sicilians turned them around and shoved them out of the harbor, whereupon the sickening sailors commenced a historically catastrophic tour of European harbors.  The results were the same for Frenchmen, Italians, English, as de Piazza recalled: “The aforesaid pest appeared in such strength..that not only the pustules, which are called in the vulgar tongue antrachi [burn, boil] but also glandular swellings arose on various members of the body, now groin, others on the legs, arms, and the throat..After this putrefaction and the deficiency of the humors, the victims gave up the ghost. Indeed this disease lasted three days; but by the fourth day at the latest the above mentioned victims had passed from human affairs.”

In the Decameron, Giovanni Boccacio wrote: “At all events, few of those who caught it ever recovered, and in most cases death occurred within three days from the appearance of the symptoms we have described.” Louis Sanctus (Louis the Saint), a friend of the poet Petrarchus, noted that “whenever one infected person dies, all who see him during his illness, or visit him, or have any dealings with him in any way, or carry him to his grave, straightaway follow him [to their deaths] without any remedy.”

Just as most authorities tended to put the blame for the plague at the feet of God (or rather of humans, for it was served up by God because of human misdeeds), many also pointed to outgroups among them as scapegoats, the primary source of divine displeasure, most notably the Jews.

Pogroms in Europe were the results of a hysteria at the outbreak of plague and an almost total lack of understanding about its origins. In Strasbourg in 1349 nearly 1000 Jews were burned in a Jewish cemetery. Amazingly, these persecutions were usually carried out with official sanction, from municipal or religious leaders. However, magistrates soon began to have doubts about the “evidence” upon which Jews were bing killed, and this curtailed the persecutions. Along with persecution, the flagellants popped up at about this time, as another kind of reaction to the plague. They continued throughout the fifteenth century, marching through Europe, proclaiming the need for repentance and thrashing themselves until they bled.  But by the 1390’s the Church–alarmed by them– had taken control of most flagellant groups and moderated their behavior, making them much more respectable.  In general, then, as plague historian Paul Slack argues, after the initial wave of the Black Death had passed, plague outbreaks became almost familiar, “people adjusted their behavior and adapted their ways of thinking so that they could accept them –not as something commonplace or everyday, but as inescapable facts of life. Plague was being accommodated.”

Another historian, Samuel Cohn notes a marked change in mentality towards the plague after 1350. Gone is the hysterical talk of floods of snakes and toads, of biblical disasters, or even of God. Instead plague commentators  during an outbreak in the 1360’s began describing the events with detailed observations, drawing more optimistic conclusions and noting similarities between cases. The god-moves-in-mysterious-ways explanation was not gone for good, but the observable causes were given more space in commentaries, such as some kind of transmutability through overcrowding, unsanitary conditions and vulnerability.

Human resistance does not seem to have improved the odds much. But human behavior seems to be the more likely reason that later plagues of the seventeenth century were restricted to a few major cities. Mortality was still high–the outbreak in Genoa and Naples in 1656-7 killing half the population, and one-fifth respectively in London and Moscow in 1665 and 1771. But authorities, even if initially sanctioning the usual scapegoating of Jews, soon moved on to more helpful actions such as quarantine, control of population movement and public hygiene. These ideas were not completely new, even in the sixth century, merchants and others were restricted from leaving Marseille and taking plague with them.   But by the fourteenth century an even more developed sense of public heath appeared especially among the Italian cities. “Much of what we understand by public health,” says Paul Slack,  “its basic rationale and ideology, was first formulated in the context of plague, and in the first decades of the second pandemic.  If the history of plague has a wider significance, it lies in that achievement.”

The big idea, gleaned from the Black Death experience in Europe, was that government had a major role in prevention of plague and care of the sick. Did the plague generate public health as an idea? Or were Europeans already open to the notion of a government role in their health? Who else had the resources to respond to a tragedy of such scope? 

There are few precedents for how to deal with plague, apart, as Slack points out, from traditional treatments for leprosy, mostly sanctioned by the Old Testament.  ‘They must have learned something also from empirical observation of the ways in which plague spread rapidly across space.”  The Italians were in the vanguard of the governmental response effort. Florence and Venice, in 1348, set up special health commissions to deal with the disease. Ideas about quarantine were central, removing infected people from public spaces and restricting movement. Needless to say there was a trade off from the point of view of citizens: such government involvement came with a restriction of “liberty” in exactly the same way that increased monitoring of our modern society is deemed necessary to combat terrorism.

Quarantine proper seems to have begun in what is now Dubrovnik (then a Venetian colony), in 1377, when newcomers were isolated for thirty days. Ten years later Marseille instituted a 40 day quarantine –the origin of the term–for ships in its harbor. Milan went further. It actually attempted to identify contacts of plague victims and segregate them. This was done even though the notion of contagion was not fully accepted–many physicians considered plague to arise from a putrefaction of the “humors” of individuals. But Milan’s ducal physicians expounded a theory of contagion. However that contagion actually took place, via touch, or breath, or “miasma,” one could avoid it by separation.

Such prevention clearly had implications for the size and purview of government. As the experience of Milan showed, controlling plague meant systematic surveillance and segregation.  Other European cities follow suit in implementing plague ordinances: Barcelona in 1408 and 1451, Antwerp in 1450 and Rouen in 1512. England, with a centralized government–embodied by Henry VIII– issued proclamations against “contagious infections” in 1518. Advised by physicians from Padua, the English parliament authorized watchmen to use violence  to keep the infected shut up at home. Wandering around with open sores was a hanging crime.

Such government concern for public health grew by leaps and bounds. By the mid seventeenth century in France, magistrates were considered the “true physicians of the people.” In a treatise on plague from 1647, the state was obliged to use “draconian methods” in the interests of public heath, because the state always preferred the “general interests to the particular.”

Perhaps one of history’s grandest movements of governmental protection from the plague was the Austrian cordon sanitaire constructed between 1728 and 1770. Similar sanitary cordons had been used before (such as at Marseille which did not protect the city, but did prevent plague from leaving it). In the Austrian case, the protective border insulated the Austro-Hungarian empire from the Ottoman regions–Anatolia and parts of the Balkans–in which plague was still endemic. “Nothing,” says Paul Slack, “could demonstrate more clearly the prima facie case that this was what freed most of Europe from plague in the 18th and early 19th century.”

Ultimately, we still know far too little about contagious diseases and the factors which render them catastrophic. Epidemiologists and governments are constantly on high alert for diseases which threaten to wipe out millions of lives, and the world we are creating throws up new opportunities for disease as our population grows and mixes. However, without the adaptability that we have shown so far in the face of pandemics, we might not be here to fight them at all.

Further Reading:

John Aberth, The Black Death: The Great Mortality of 1348-50:  A Brief History with Documents

Paul Slack, Plague, A Very Short Introduction

John Kelley, The Great Mortality: An Intimate History of the Black Death, the Most Devastating Plague of all Time. 

Boccaccio’s Decameron

Samuel Pepys, Journal of the Plague Year

About the Author
Adrian Cole studied Arabic at Exeter University in the UK, Alexandria, Egypt and Harvard University. He is now a freelance writer, living on an island in Casco Bay, Maine, with his wife and children. His book The Thinking Past was published by Oxford University Press in 2014.
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