The Black Plague is what historians have come to call a brutal bubonic plague pandemic that swept across Europe in the middle of the 14th century. The sickness is thought to have first arrived in Europe via ships that sailed through the Mediterranean into modern-day Italy. It spread like wildfire among Sicilian people and then rushed onto mainland Europe.
Over just a few years in the very middle of the 14th century, the bubonic plague killed at least 20 million people—which would have represented more than a third of the population of Europe at the time. Major cities like London and Paris lost nearly half their population in less than a decade. Isolation was nearly impossible in urban areas, and the plague spread quickly. Those living on the margins of society suffered brutally, were killed in droves, and left behind nothing but devastation in their wake.
More than 500 years after the “Black Death” ravaged the continent, researchers have finally started to learn more about where it came from. In 1885, scientist Alexandre Yersin discovered the Yersinia pestis bacterium while experimenting in his lab. That little killer was quickly outed as the source of the Black Plague. With it came a groundswell of scientific information and historical revelations about what really happened back in the mid-1300s.
Thankfully for those of us living today, antibiotics have been developed to treat the plague. Sufferers who get to a doctor’s office quickly can recover fully. But the people living in 14th-century Europe were obviously not that lucky. Millions suffered miserable sickness, then sepsis, and eventually organ failure leading to death. In this list, you’ll learn all about the real story behind the Black Plague. Let’s tackle ten misconceptions about its cause, spread, and treatment—and correct the historical record about one of the world’s worst-ever pandemics.
10 A Plague By Any Other Name…
The plague wasn’t confined to the approximate four-year period between 1347 and 1351. In reality, it actually made at least three major appearances throughout modern history—and likely several lesser ones. The first known plague pop-up came way back in the year 541. It wasn’t known as the Black Plague or the Black Death at the time, though. Instead, it was called the Plague of Justinian, named not-so-nicely after then-Byzantine emperor Justinian I.
Over the next 50 years, Justinian’s Plague killed millions of people. It mostly died out by about 590, but its effects on Constantinople were devastating. So when it popped back up 800 years later, some church records and other documentation recalled its horrible effects. Even then, by the 1340s, the plague was merely known as “the pestilence” at the time.
Today, historians believe that name came about because of what it did to unlucky host bodies. Sick people would hemorrhage blood and suffer gangrene which often turned into a deadly infection. That name stuck among Europeans as they tried to fight it off.
The awful sickness didn’t actually become known by the masses as the “Black Death” until centuries later. Some historians have pondered the possibility this name came from the Latin expression atra mors, with “atra” meaning black or terrible and “mors” meaning death. That’s a strong possibility, considering the name was being used in non-Latin-speaking enclaves during the 14th century.
The French physician Simon de Covino called it the mors nigra in an infamous poem he penned in 1350 to commemorate the horror of the time. By the 19th century, that had long become the preferred name. Both English and Spanish literature from the 1800s refers to the plague by variations upon that “black death” root term.
9 Don’t Blame the Rats!
We don’t blame you if you think rats were the source of the Black Plague. But we will blame you if you still believe that after reading this list. The blame game here is at least somewhat understandable. For centuries, scientists thought swarms of rats spread the disease to humans. Infected fleas, the theory went, jumped from rat to rat—and then rat to human—and ended up killing millions. But for a few decades now, researchers have come to believe that actually wasn’t how it happened at all.
For one, rats weren’t nearly as common in 14th-century cities as you might have thought. Historical records reveal there were very, very few rodent problems in major cities. Plus, any rats that did travel with ships almost certainly would not have made it into town centers. It’s far more likely they would have stayed in ports of call, where any close contact with humans would have been much less likely.
So, how did the Black Death spread, then? Today, scientists believe it was good old-fashioned human-to-human contact. The flea theory holds up, but not via rats. Instead, the mass death was almost certainly spread by human-based fleas and lice that ran rampant at the time. This would seem to make sense too. After all, humans came into contact regularly with each other then as they do now. And in cities, especially, there were mass populations of people who lived in very close quarters.
In those conditions, fleas and lice spread fast from one infected person to another and carried the disease right alongside. Before too long, humans were infecting each other at nearly unbelievable rates. Those infections were happening en masse in northern European cities, too—places where the rat population was nearly non-existent. So basically, it seems like rats have gotten a bum rap for nearly seven centuries!
8 Instead, Blame Transportation
While rats didn’t spread the plague far and wide, improvements in human transportation did. At its most viral point, the Black Death was spreading as quickly as 24 miles per day. Improvements in transportation routes and an increased focus on inter-regional commerce at the time actually made its spread quite a bit worse than what would have happened even decades before.
By the 14th century, people across Europe used horses and wagons to transport goods from town to town. Roads were not nearly as good as they are today, of course. But the avenues of commerce were expanding rapidly at the time. With it came the mass movement of people—and the mass spread of death. It wasn’t just an issue for Europe, either.
Experts now recognize that the opening of the Silk Road allowed the plague to spread much further and faster than any sickness before it. Between new overland routes like that and increasing maritime sophistication, humans were interacting more and spreading germs faster than anyone had ever experienced.
And improved transportation was only half the issue. Because trade routes were fast becoming better, more people had been moving to cities at the time the plague took hold. Europe was (slowly) changing from a rural region to one with more urban centers of commerce. Those new city dwellers packed themselves in closely. So when the plague hit one family, it quickly touched all.
Then, because of the day’s focus on religious endeavors, plague carriers would spread the sickness even further at pilgrimage sites. Thousands of people from various communities reached the pilgrim spots, worshiped together, and brought the plague home to their families and neighbors. As the 1340s went on, the sickness spread across Europe and devastated nearly every city in its path.
7 People Didn’t Just Wait to Die
For several years, the plague swept its way across the continent and was completely unstopped in its path of destruction. But that didn’t mean people took it lying down and decided to do nothing. In fact, Europeans of the time did quite a bit to try to mitigate its deadly effects. The Italians set up large-scale “trentino” periods, which were 30-day isolation holds for affected regions. When those didn’t work, they moved to the 10-day longer “quarantino” period. Does that word look familiar? It should.
That 14th-century Italian practice to cut down on plague deaths gave us the modern-day word for “quarantine.” In Milan alone, city officials became remarkably active in trying to stop the plague. They put together even stricter quarantines for locals. Then, they forbid all pilgrims and other travelers from entering the city gates. Doctors traveled throughout the city and monitored the plague’s spread. It was nothing compared to today’s pandemic policies. But for the 14th century, Milan proved to be a remarkably forward-thinking place.
Another city where plague sufferers took action against their awful fates was Dubrovnik. The southern European town, which is in present-day Croatia, was known as Ragusa at the time and held under Italian rule. In the 1370s, about 20 years after the Black Death first waved across Europe, Dubrovnik suffered a second outbreak. The city immediately acted by fencing off their seaport with new rules: a 40-day “quarantino” for all travelers.
Visiting ships had to idle out at sea for nearly six full weeks before they were allowed to drop off their goods. The city later put together a series of penalties for residents guilty of breaking “plague laws.” They even hired guards to patrol the city gate to prevent sick people from entering.
6 It (Probably) Didn’t Produce THAT Nursery Rhyme
Yes, we’ve all heard that famous nursery rhyme. “Ring around the rosie / A pocket full of posies,” it starts, as little children for centuries have circled around each other during play. “Ashes, ashes / We all fall down.” As rumor would have it, that rhyme is supposedly a very dark reference to the Black Death. The ring of roses is said to refer to a rash, and the “ashes” line is supposedly actually an altered reference to a sneezing sickness that was brought on during the plague’s terrible run.
Then, of course, it doesn’t take much to imagine what “we all fall down” could mean. But folklorists have long tried to turn back that persistent rumor about the nursery rhyme’s supposed plague origins. In fact, many modern historians now agree that the rhyme is far too modern to have ever been connected to any culture even close to 14th-century Europe.
This nursery rhyme’s supposed plague origin story was first mentioned in print in the Oxford Dictionary of Nursery Rhymes written by Iona and Peter Opie in the early 1950s. However, in their dictionary entry, the Opies were very skeptical that the rhyme had anything to do with the plague at all. They felt it had been created centuries after the Black Death rushed through Europe. Contemporary historians agree too.
Many folklorists point to the fact that there are many “happier” versions of the rhyme floating around too. In one verse, the third and fourth lines read, “the one who stoops last / shall tell whom she loves best.” Another version claims the lines go, “all the girls in our town / ring for little Josie.” Researchers are befuddled by why the rhyme has been connected to a 700-year-old plague at all. And yet the legend persists!
5 The Plague Went on Longer Than You Think
As we’ve already learned, the Black Plague appears to have started way back in the year 541 under the emperor Justinian. For the next eight centuries, it lay (mostly) dormant but would pop up every now and then, affecting small towns or villages in horrific ways. The centuries of chaos were spread so far and wide that it was tough to get a feel for the plague as a pandemic. But the danger was ever-present.
Today, scientists think the Black Plague may have killed as many as 100 million across the eight centuries between Justinian’s reign and the 14th-century terror. More recent research into the Yersinia pestis bacteria has found the very same microorganism was responsible for all three major pandemics: Justinian’s plague, the 14th-century Black Death, and a major spread in the early 19th century. After lying dormant for long periods, the bacteria simply came back to prominence at seemingly random times after surviving in certain conditions.
And the bubonic plague still exists today. Cases are actively being tracked from around the world. Between 1970 and 2020 alone, the Centers for Disease Control reported that nearly 500 cases of bubonic plague were reported in the United States. Most of those occurred in rural western areas of the country.
More recent outbreaks have led to small pockets of death in other places around the world too. In 2021, the plague infected 100 people and killed 13 in the Democratic Republic of Congo. Another 60 cases were documented in Madagascar that year, too.
4 Forget about Those Bird Beaks
Even if you know very little about the plague, you know all about those bird-like beaks. Plague doctors were said to go around town in bird-looking masks and ominous all-black outfits. Later literature was renowned for offering descriptions and images of these scary-looking medical professionals trying in vain to beat back against the Black Death. But the reality is that these bird masks and the medical men who wore them weren’t around for either Justinian’s plague or the 14th-century Black Death.
In fact, they don’t actually appear in any kind of documentation until the 17th century. Roughly 300 years after the Black Plague, writers began embellishing their stories with tales of these supposed masked crusaders. It was during that time, too, that physicians actually began wearing the costume in real life. They donned those unique, long-nosed masks in the hopes of avoiding a minor revival of the plague in Paris in the early 1600s—but certainly not centuries earlier during the world’s most famous pandemic.
The credit for the notorious outfit ought to be given to French physician Charles de Lorme. In the early 1600s, he designed what many at the time felt was a completely impenetrable medical costume. The heavy overcoat was covered in wax. Tall boots, a goat leather hat, and gloves were all worn to protect the extremities. And the beaked mask was meant to top it all off.
The beak was actually hollow on the inside. Doctors would use the hollowed-out opening to insert a mix of herbs and medical ointments from that time period. They thought the compounds might give them a filter to fight infection and protect themselves while working with sick people. Of course, the beaks didn’t work. Doctors didn’t know about bacteria like we do today.
Instead, they felt the beak masks stuffed with glorified incense could filter out “evil smells,” which were thought at the time to be what spread disease. Had they known then what we know now, they would have realized how ineffective the beaks actually were. But regardless, those memorable masks did not make any appearances during the 14th-century Black Death.
3 The Plague Didn’t Kill Indiscriminately
The sheer raw numbers bandied about as the plague’s death toll might make you think it killed literally everyone in its path. But that’s actually not true. Today, the bubonic plague has become remarkably easy to treat. Sufferers are given antibiotics, and those medicines kill the plague quickly in the majority of people. But even back then, the Black Death was somewhat less lethal than we have come to believe.
Scientists have dug up gravesites from plague times to find remarkably consistent conclusions across a variety of populations. The plague was actually pretty selective in how it spread and who it killed. Much like other pandemics and viral diseases, the plague preyed on the very young, the very old, and those who were already weakened and unhealthy.
In one study, scientists dug up nearly 500 skeletons of plague sufferers. The majority showed signs of “frailty” during their lives, including obvious malnutrition, changes in bone density that suggested other viral infections, and notable lesions on the skeletons. Scientists used those observations to realize the plague most often killed people who were already in poor health. Of course, medicine in the 14th century was nearly non-existent for most people—especially among common laborers and farmers.
So the “frail” cross-section of the population extended far beyond what we might see today. That, in turn, is why the plague’s death toll was so remarkably high. But judging by these skeleton reveals of the modern era, it would seem that able-bodied 14th-century people had a significantly better shot of surviving the Black Death as it ravaged around them.
2 Most People Didn’t See It as God’s Wrath
It is no surprise to know that 14th-century people were largely caught up in a mix of religion and what we would consider superstition. Faith in both God and the unknown was a common part of everyday life back then. And that focus on the spiritual realm would have led many people to ascribe the plague to a higher power. Right? Well, maybe not as much as you’d think. It’s true that many people believed the bubonic plague was “a punishment from God.” Many more believed that to be saved from certain death, they had to ask the Lord for forgiveness and spiritually cleanse themselves.
This cleansing took many forms at the height of plague hysteria. Processions of traveling Jesus followers would beat themselves openly in public in the hopes that their self-flagellation would “save” local populations. In Germany, large mobs of people wiped out full neighborhoods of Jews in 1348 and 1349 because they believed these outsiders were responsible for the plague. Many more prayed openly and threw themselves prostrate for God in a vain attempt to stop the pestilence.
Doctors knew better, though. Even though medical knowledge was remarkably limited in the 14th century, the medical professionals who did live at that time didn’t buy the “God’s punishment” theory alone. Medicine at that time was based on the idea of “humors.” Contemporary experts thought all diseases were linked with various bodily fluids, like blood, bile, and mucus. Doctors felt the plague was inextricably connected to one of those things—and not, say, to God.
The problem was these early medical pioneers had very little with which to soothe and save patients. All they could really do for plague victims were procedures like bloodletting. That act, done in the vain hope of removing tainted plague blood from the body, rarely ever worked out to any success. Other doctors believed they had to fight off “miasma,” or unhealthy air, in order to ward off the plague. For some patients, they counseled burning scented wood or bathing in pungent rose water to drive away plague fumes and restore the body.
1 Europe Wasn’t the Only Hotspot
Much of the current-day study of plague history is dominated by European documentation. It’s true that many millions of people died on the continent. After the Black Death burned through the region, it remade entire cities and forever altered European history. But it wasn’t the only place where the plague took hold. Scientists now believe the plague actually started in Asia years—or even decades—before sailors brought it to the Italian coast.
Simultaneously, the Black Plague made its way west across the Silk Road and other overland trade routes too. Those trade routes branched off to connect to other far-flung places like Turkey and China—and the plague made terrible appearances in those locales as well. The real shocker came in 2022 when a group of scientists published a new study in the journal Nature.
They believe in having found what would be the earliest-identified plague strain in Kyrgyzstan. They analyzed DNA from human bones dating back to 1338. Those skeletons tested positive for the bacterium that causes the plague. It’s a major breakthrough, and if their research is true, it’s very possible the plague originated on the steppes of Central Asia near the Tian Shan Mountains.
By the middle of the 14th century, the plague was moving so quickly that it simply couldn’t have been contained to Europe. In the middle of the roughest plague period during that century, historical documents report plague deaths in East Asia, the Middle East, and Northern Africa. There, the plague appears to have killed at least as many people as it did in Europe. With the presence of undocumented slaves and laborers from sub-Saharan Africa, it’s likely far more were killed than historians will ever know about.
Some researchers even say the plague went as far south as the southern ends of Africa, killing natives there who had previously been mostly unspoiled by jungle and Serengeti life. Historical documentation is lacking in those areas, but modern-day researchers have pointed to abandoned settlements and archaeological discoveries as proof of a major pandemic sweeping down the African continent.