Explained: What was the Black Death, where did it originate?

What was the Black Death?

The term Black Death refers to the bubonic plague that spread across Western Asia, Northern Africa, Middle East and Europe in 1346-53.

Most scholars agree that the Black Death, which killed millions, was caused by bacterium Yersinia pestis and was spread by fleas that were carried by rodent hosts.

The microorganism Y. pestis spread to human populations, who at some point transmitted it to others either through the vector of a human flea or directly through the respiratory system.

Contemporaries who wrote about the epidemic, often described the buboes (hard, inflamed lymph nodes) as the distinguishing clinical feature.

Matteo Villani, the Florentine chronicler, referred to the disease in 1348 as the ‘mortal disease of buboes’ and ‘pestilence of buboes’.

The onset of symptoms was followed by intense fever and vomiting of blood. After the initial infection, most victims died within 2-7 days.

How did researchers pinpoint the Black Death’s origin?

In the late 19th century, excavations of two Christian cemeteries near Lake Issyk-Kul in Kyrgyzstan unearthed a settlement of a trading community that had been affected by an unknown disease in 1338-1339.

Historian Philip Slavin, one of the researchers involved in the present study, examined the tombstones, on which Syriac inscriptions stated that the victims died of an unknown epidemic or “pestilence”.

The researchers then extracted DNA from the teeth of seven people that were buried at the cemetery and found genetic traces of Y. pestis bacterium.

The extracted DNA was compared with bacterial DNA collected from other plague victims in Europe. The researchers found that the strain of Y. pestis that caused the epidemic in the settlements near Lake Issyk-Kul was the direct ancestor of the strain that caused the Black Death, according to the Wall Street Journal.

By piecing together the Y. pestis genome from the cemeteries in Kyrgyzstan, researchers found a single plague strain that can be placed at the beginning of the Black Death outbreak before it spread to Europe years later.

“We found the Black Death’s source strain and we even know its exact date (the year 1338)”, said Maria Spyrou, lead author of the report.

Why is the new discovery significant?

The geographical origin point of the plague has been debated for centuries. Some historians have argued that the plague originated in China, and spread across Europe by Italian merchants who first entered the continent in trading caravans through Crimea.

According to another contested theory based on a 1348 memoir of an Italian notary from Piacenza, it has been argued Mongol army hurled plague-infested bodies into the city during the siege of Caffa (Crimea) and led to spread of the disease.

Historian Mary Fissel told The New York Times that if the latest research is correct, it would mean that the plague spread through trading routes and not, as some historians have argued, through warfare a century prior.

Why was this plague called the Black Death?

It is commonly believed that the term Black Death gets its name from the black marks that appeared on some of the plague victims’ bodies. However, historians argued that this term, which only emerged centuries later, had less to do with the disease’s clinical symptoms, and more to do with how European writers from the 19th century onwards understood the epidemic.

In the 14th century, the epidemic was referred to as the ‘great pestilence’ or ‘great death’, due to the demographic havoc that it caused.

Historian Nukhet Varlik argues that the term Black Death was devised by European writers in the 19th century, becoming widely accepted as time went by. German physician Justus Friedrich Carl Hecker is credited with universalizing the term in his 1832 book Der Schwarze Tod (Black Death), which was translated to other languages as well. He presented the Black Death as a unique plague, distinct from any other disease that came before it.

Varlik argues that the world black also carried a dark, gloomy emotional tone, due to the sheer amount of deaths generated by the plague.

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How deadly was the spread, what was its aftermath?

Due to a lack of comprehensive historical data from that time, it is difficult to know the exact death toll. Norwegian historian Ole J Benedictow, who wrote extensively on the disease, estimated that around 60-65 per cent of Europe’s population or 52 million people died due to the plague.

Describing his experience from Siena in 1348, Italian chronicler Agnolo di Tura wrote: “Great pits were dug and piled deep with the multitude of dead. And they died by the hundreds both day and night.”

A dramatic reduction in population was accompanied with huge economic and social changes in Europe. With a smaller labour force available, wages went up, leaving ordinary people with a higher economic surplus.

The Black Death also led to an increase in religious persecution of the Jews, who were blamed for spreading the contagion.