The Black Plague

If the Black Plague sounds terrifying to you, it should. The Black Plague killed millions rapidly and came with symptoms that would give anyone nightmares. It spread from Asia to Europe, leaving lasting impacts in its wake. But what was the Black Plague and how did it manage to spread so quickly? Let’s answer these questions and then we’ll look at the change it prompted in Europe.

The Black Plague Definition

The Black Plague, also known as the Black Death, was a bubonic plague pandemic that broke out across Asia, Europe, and North Africa in the 1330s. It originated in Asia and reached European shores in 1347 when ships filled with ill and recently deceased sailors arrived in Sicily. The Black Plague quickly spread to other Italian port cities, and soon, the entirety of Europe. It decimated populations wherever it went and estimates show that as many as one in three Europeans died as a result of the Black Plague.

Fig. 1 - Drawing of a saint visiting plague victims²

The Black Plague Time Period

The Black Plague occurred in what we know today as the Middle Ages, after the control of the Roman Empire, but before the Renaissance had taken hold of Europe. Exact dates are tricky when we look at history this old, but we know that the Black Plague originated in Asia in the mid-1330s and arrived in Europe in 1347. Once in Europe, the Black Plague remained at endemic levels until it dissipated in the early 1350s.

The Black Plague Causes

We know now that the actual cause of the Black Plague infection was a bacterium called Yersinia pestis. The bacteria spread from human to human through flea bites and could also cause secondary forms of infection (the septicaemic plague and the pneumonic plague) through the air. Of course, this still doesn’t answer the question of how bacteria originating in Asia made it all the way to Europe.

The fleas that housed the deadly bacteria often found their own homes on rats. And some of these rats found themselves on ships traversing between continents.

Fig. 2 - Map of Late Medieval trade routes

The Black Plague Causes: New Trade Networks

Advances in banking and transportation (e.g. better boats and roads) allowed for the expansion of new trade networks and streamlined versions of old trade networks. Additionally, the Silk Road that had been in use since Roman times was under Mongol control. This meant that Asia and Europe were interacting more than ever before. It also meant that the Black Plague was able to spread from continent to continent with ease.

The Black Plague Causes: The Spread in Europe

European cities were often overpopulated which meant the Black Plague was able to spread from person to person with ease. Additionally, conditions in these overpopulated cities were less than sanitary. Garbage and human waste lined the streets and rats (with their infected fleas) ran rampant.

The Black Plague Causes: Summary

The Black Plague Symptoms

Symptoms depended on the type of plague but the bubonic plague was the most prevalent. It came with many typical symptoms of illness including:

• fever
• chills
• vomiting
• body aches
• fatigue

But that was certainly not all. The most horrific and characteristic symptom was the "buboes" or lumps located on the groin, armpit, and neck. They were extremely large (think egg size) and seeped blood and pus. The populace at the time had no way to know that these lumps were swollen lymph nodes.

The Black Plague Impacts

The Black Plague certainly had major effects on the population that experienced the pandemic, but it also led to lasting impacts experienced by later generations.

Short-Term Black Plague Impacts

The most apparent short-term impact of the Black Plague was the huge loss in population. For a time, all work stopped and trade routes ran dry. Europeans were living in fear of their neighbor.

The Black Plague lost its strength in the early 1350s. The extreme population loss, however, caused a labor shortage that almost led to a collapse of social structures in Europe. Feudal lords were in desperate need of workers. This gave serfs bargaining power and they were able to demand wages for the first time. They could then spend these wages in town, enriching a newly forming middle class that included merchants and artisans.

Long-Term Black Plague Impacts

It would take over a century for the population of Europe to return to its post-pandemic levels and the feudal system remained shaken. The middle class continued to grow and thrive as trade expanded even further and the pool of workers with buying power grew. The impacts of the Black Plague effectively sped up the path of social and economic development in Europe.

Historiography of the Black Plague

Although the dominant historical opinion is that Yersinia pestis caused the Black Plague, not all historians agree. For example, historian Samuel Cohn argues that Yersinia pestis couldn't have been the cause because of the Black Plague's uncharacteristically rapid spread and the discrepancy in symptoms compared to the modern-day bubonic plague. But then what caused the black plague? There is no general agreement but one theory posed by historian Graham Twigg suggests it could have been anthrax poisoning.