Late Middle Ages

How Europe finally escaped the cycle of plague

The last great outbreak of plague in Western Europe began on a Tuesday in May 1720. The ship Grand Saint-Antoine had arrived at the quay of Marseilles after a long voyage from Sidon and Tripoli, carrying a cargo of silk, cotton, and a small but lethal cargo of Yersinia pestis in the bodies of the rats in its hold. The local bureau de santé was under intense pressure to admit the ship: the cargo was valuable, the merchants were influential, and a public fast had recently been held to implore God’s blessing on the city’s commerce. The ship was allowed to enter. Within weeks, the dockside district was in the grip of an epidemic. Within months, the plague had spread into the old town. Within two years, perhaps 50,000 of the 90,000 inhabitants of Marseilles were dead, and the disease had spread to Aix, Arles, Toulon, and a dozen other towns of Provence. The outbreak was the last great plague of the West, and the response to it was both desperate and revealing.

The wider context of the recurring waves of plague is set out in Recurring plagues and their decline and in Why did the plague return in waves?. The saints and folk beliefs of the late medieval response are treated in Late medieval plague saints and folk beliefs. The medical response, which was transformed during the long period of decline, is examined in Medieval medical responses to the Black Death.

A Mystery of Demographic History

The decline of plague in early modern Europe is, in some ways, a more difficult problem than the original Black Death. The catastrophe of 1347–1351 can be explained, at least in outline, as the introduction of a new pathogen into a population with no acquired immunity. The decline, by contrast, was not the result of any single medical intervention, since germ theory and antibiotics lay centuries in the future. It was the result of a complex set of ecological, architectural, institutional, and demographic changes that worked together, over centuries, to reduce the vulnerability of the European population and the European environment to the disease.

The puzzle of the decline has been the subject of a long historiographical debate. The English historian J. F. D. Shrewsbury, in A History of Bubonic Plague in the British Isles (1970), argued that the disappearance of plague was essentially a consequence of the disappearance of the black rat, the principal reservoir of the Yersinia pestis bacterium. The Norwegian historian Ole J. Benedictow, in The Black Death 1346–1353: The Complete History (2004), challenged the older population estimates of Josiah Russell and others and argued that the Black Death killed a much larger proportion of the European population than had previously been thought; the implications of his work for the question of decline are still being worked out. The French historian Jean-Noël Biraben, in Les hommes et la peste en France (1975–1976), documented the long-term decline in detail and showed that the disappearance of plague from Western Europe was the result of many overlapping factors. Samuel K. Cohn Jr., in The Black Death Transformed (2002), argued for a more cultural reading, in which the decline of plague was bound up with the transformation of European medical and religious practice.

The most recent scholarship, exemplified by the work of John Hatcher and of the contributors to the Cambridge History of the Black Death (edited by Mark Bailey, 2015), tends to a multi-causal account. The decline of plague in Western Europe was the result of a combination of changes — in the rodent population, in housing, in public health, in climate, in demography, and in trade — that together reduced the vulnerability of the European population to the disease. The story is therefore not a story of a single breakthrough, but of a long, slow, and uneven process of adjustment.

The Black Rat, the Tiled Roof, and the Brown Rat

The most commonly cited factor in the decline of plague is the change in the rodent population of Europe. The black rat (Rattus rattus), the principal reservoir of the Yersinia pestis bacterium in medieval Europe, was a commensal species that lived in close association with humans, infesting thatched roofs, timber-framed walls, and the holds of ships. The brown rat (Rattus norvegicus), a larger and more aggressive species that arrived in Europe from Central Asia in the early modern period — probably in the baggage trains of the armies of the early eighteenth century — competes with the black rat and tends to displace it. The brown rat is less prone to harbour the Yersinia pestis bacterium and less prone to live in close association with humans: it prefers cellars, sewers, and the banks of rivers, and it is less likely to enter the human dwelling. The slow replacement of the black rat by the brown rat, between the late seventeenth and the early nineteenth centuries, would have reduced the opportunities for the transmission of the disease.

The change in the rodent population was accompanied by a change in European housing. The thatched roofs and timber-and-wattle construction of the medieval house were gradually replaced, in the seventeenth and eighteenth centuries, by tiled roofs, brick walls, and stone foundations. The change was not uniform: the rural houses of the European periphery remained largely timber-framed well into the nineteenth century. But the urban houses of the major cities of the European plain were rebuilt in brick and tile, and the change would have reduced the opportunities for rats to live in the roofs and walls of the houses, and the opportunities for fleas to infest the interior. The change is one of the reasons why the great urban outbreaks of the seventeenth century — in London in 1665, in Naples in 1656, in Amsterdam in 1663 — were the last of their kind in Western Europe.

A third factor was climate. The early modern period saw a significant cooling of the European climate, often called the Little Ice Age, with the most severe phases in the late sixteenth and the seventeenth centuries. The cooler weather may have reduced the opportunities for the Yersinia pestis bacterium to multiply in the flea and the rat, and the association of the worst European outbreaks of plague with periods of mild, wet weather is well documented by historians such as Jean-Noël Biraben and by the paleoclimatologists. The cool, dry weather of the late seventeenth and early eighteenth centuries may have made outbreaks less likely. Climate is not, on its own, an explanation of the decline, but it is one of the contributory factors.

Quarantine, Lazarettos, and the Sanità

The most important institutional factor in the decline of plague was the development of an effective public health apparatus. The first permanent sanità was established in Venice in 1486; by 1600 nearly every major Italian city had a permanent health board. The boards had the power to isolate infected households, to restrict the movement of travellers, to seize and burn the clothing of the dead, to appoint plague doctors, and to declare quarantines. The famous quarantine — the quaranta giorni, the forty-day period of isolation imposed on incoming ships, travellers, and goods — became the standard instrument of public health in the early modern Mediterranean.

The lazaretto, or plague hospital, was the second key institution. The first permanent lazaretto was established in Venice in 1423, on the island of Santa Maria di Nazareth, and the term lazaretto is derived from the name of the patron saint of the hospital. The lazarettos of the Italian cities — Milan, Genoa, Rome, Naples, Palermo — were substantial buildings, often several storeys high, with separate rooms for the infected, for the suspected, and for the convalescent. They were used to isolate the sick, to keep the contacts of the sick away from the rest of the population, and to provide a place for the sick to be cared for. The lazarettos were not always effective, and they were often overcrowded and underfunded, but they were the first systematic attempt to provide institutional care for the victims of epidemic disease.

The public health apparatus was not, of course, a perfect instrument. The cordons sanitaires of the early modern period were often evaded, the quarantines were often bribed, and the lazarettos were often incubators of disease rather than instruments of containment. But the apparatus was, on the whole, effective enough to limit the spread of the disease, and it became more effective over time. The Marseilles outbreak of 1720, for example, was eventually contained by a strict cordon sanitaire around the city, imposed by the Parlement of Aix and enforced by the French army. The cordon held. The plague did not spread to the rest of France.

The Last Outbreaks: London 1665 and Marseilles 1720

The great plague of London of 1665 is the most thoroughly documented outbreak of plague in early modern Europe. The outbreak is known in detail because of the parish records, the bills of mortality, and the diary of Samuel Pepys, who watched the plague sweep through the city from his office in Whitehall. The mortality of the outbreak is usually estimated at 100,000, or roughly a quarter of the population of the city. The outbreak was eventually contained by the Great Fire of London of September 1666, which destroyed much of the rat-infested timber housing of the medieval city and made possible the rebuild in brick and stone that the new public health demanded. The Great Fire of London is, in this sense, one of the most important public health events in the history of early modern Europe.

The great plague of Marseilles of 1720 was, as already noted, the last major outbreak of plague in Western Europe. The outbreak began on the quayside in May 1720, with the arrival of the Grand Saint-Antoine. The local bureau de santé was abolished by the Parlement of Aix in October 1720 for its failures, and a new Conseil de Santé was established. The cordon sanitaire was imposed in November 1720, and held until the spring of 1722. The outbreak was eventually contained, and the plague did not spread to the rest of France. The response to the Marseilles outbreak is a model of the early modern public health apparatus in action: the cordon sanitaire, the lazaretto, the appointment of plague doctors, the burning of the clothing of the dead, the strict isolation of the infected households. The apparatus worked.

After Marseilles, the great European outbreaks of plague came to an end. The last outbreak in the British Isles was the small outbreak in Noja, in southern Italy, in 1815. The last outbreak in the Mediterranean was the outbreak in Porto, in 1899. The last outbreak in the Middle East was the outbreak in Egypt in 1947. Plague has not disappeared from the world: it is still endemic in parts of Central Asia, East Africa, and the western United States. But the great European outbreaks of the late medieval and early modern periods had ended, and the end of those outbreaks is one of the most important demographic transitions in European history.

The Demographic and Cultural Consequence

The decline of plague was, in demographic terms, one of the most important events of the early modern period. The European population, which had been held in check for centuries by the recurring outbreaks of plague, began to grow rapidly in the eighteenth century. The mortality regime of the early modern period, in which plague was a major cause of death, gave way to a new regime in which epidemic disease was associated with smallpox, typhus, dysentery, and other diseases, but not with plague. The great demographic transition of the eighteenth century, in which the European population began to grow rapidly, was made possible, in part, by the disappearance of the plague.

The cultural consequences were no less significant. The apparatus of public health that had been developed in response to the disease — the sanità, the quarantine, the lazaretto, the plague doctor — was gradually dismantled or redirected to other purposes. The cult of the saints of the plague, which had been a central feature of European religion for centuries, gradually declined. The art and literature of the memento mori, the Danse Macabre, and the transi tomb gave way to the more confident images of the Enlightenment. The art historian Philippe Ariès, in L’homme devant la mort (1977), argued that the decline of the plague marked the end of one of the dominant Western attitudes to death, and the beginning of another.

The story of the decline of the plague is, in the end, the story of how Europe learned to live with mass death, and how it eventually, painfully, and only partially, escaped it. The decline was the result of a complex set of factors that worked together over centuries to reduce the vulnerability of the European population and the European environment to the disease. The story is not a story of medical progress, in the modern sense, but a story of slow institutional, ecological, and demographic adjustment. The plague did not disappear because doctors learned to cure it. It disappeared because the conditions that had allowed it to flourish in the medieval and early modern world were gradually transformed.

References

  • Benedictow, Ole J. The Black Death 1346–1353: The Complete History. Boydell Press, 2004.
  • Biraben, Jean-Noël. Les hommes et la peste en France et dans les pays européens et méditerranéens. 2 vols. Mouton, 1975–1976.
  • Shrewsbury, J. F. D. A History of Bubonic Plague in the British Isles. Cambridge University Press, 1970.
  • Slack, Paul. The Black Death Past and Present. 2nd ed. Oxbow Books, 2012. (First published 1985.)
  • Bailey, Mark, ed. The Cambridge History of the Black Death. Cambridge University Press, 2015.