The Black Death Killed a Third of Europe — Then Humans Won

Between a third and half of Europe, dead, in roughly five years. At least twenty-five million people. If you were here for Byzantium, you

watched this killer's first strike gut Justinian's Constantinople, and at the end, I told you its descendant came back eight centuries later.

That was almost true. The genetics say something stranger: the plague that returned was not the child of the old plague. It was the same killer species, striking fresh, a second, independent jump out of the wild, from mountains

most people cannot find on a map. This is the story of the most one-sided

fight in human history. Kings lost. Popes lost. Armies, prayers, and medicine lost. And by the end, you'll

see how a disease that beat everyone ended up handing power to the people at the very bottom, and how the underdog finally won.

What gets me about this story is a pope fact-checking a conspiracy theory in thirteen forty-eight, and losing. We like to think misinformation is a modern disease. It is the oldest symptom there is. So where did the fresh strike come from?

For six hundred years, nobody knew. But the answer was carved in stone,

beside a lake. High in the Tian Shan mountains of Central Asia, wild marmots carry a bacterium in their colonies. In their blood, it is a fact of nature. In ours, it is a catastrophe.

Near Lake Issyk-Kul, in what is now Kyrgyzstan, there is an old cemetery called Kara-Djigach. Its tombstones record a spike of deaths in thirteen thirty-eight and thirteen thirty-nine. Cause of death, carved in stone:

pestilence. In twenty twenty-two, geneticists pulled ancient DNA from those graves. It was the ancestor of the Black Death, and it had not traveled from anywhere. It evolved right there, locally, in the marmot

colonies of those mountains. The killer was born at altitude, among sleeping rodents, under snow. But a bacterium in a mountain marmot cannot

end a continent. It needed a ride. And fourteenth-century Eurasia had just built it the finest road network on Earth.

If you saw our Mongol episode, you know the Mongol peace threw open the trade routes from China to the Black Sea. Grain, silk, silver, and fleas, all moved on the same roads. By thirteen forty-six, the plague reached

a khan's army. Jani Beg of the Golden Horde was besieging Caffa, a Genoese trading post in Crimea, when his soldiers began to die.

Now comes one of history's most famous stories. An Italian notary named de' Mussi wrote that the khan's men loaded the corpses into catapults

and lobbed them over the city walls. Dead bodies, arcing over the ramparts, into the streets. If true, it would be one of the first biological attacks in

history. But de' Mussi was in Italy at the time, hundreds of miles from Caffa. No one who was there wrote it down. Plague corpses are actually poor

transmitters, and the disease was likely entering Europe through Black Sea trade anyway. So hold the image, but hold it loosely.

It is a contested story. What is not contested is what sailed out

of that sea. In October thirteen forty-seven, a handful of Genoese galleys, twelve, said a friar writing ten years later, rowed into the harbor of Messina, Sicily. The oars dipped.

The ropes came ashore. So did the fleas. The citizens realized what the ships carried and drove them out of the port. Too late.

From Sicily, the plague took North Africa, Italy, Spain and France within a year. The next year, the German lands and the Low Countries.

Even the sea was no protection. A ship from England docked at Bergen, in Norway. Its crew looked healthy. But after they unloaded the cargo, the sailors began to die, and days later, so did the town.

An Icelandic cleric wrote it down. The famous version, a ghost ship drifting ashore with an all-dead crew, is later legend. The documented truth is worse: the ship looked fine.

Within about five years, the plague had swept from Sicily to Russia, a full circle back to the steppes it left. Now count what it cost.

They did not call it the Black Death. No one alive did, that name only appeared around the seventeen fifties, and the "black" meant dreadful, not a symptom. They called it the Great Mortality. The disease usually

announced itself as a bubo, a painful swelling at the groin, the armpit, the neck, and a fever. A Welsh poet wrote that the sores looked like the head of an onion, like half pence, like berries.

You have heard that rats spread it. Fleas on black rats are the classic model, but a modern study found that human body lice and human fleas fit the death curves of nine European outbreaks better than the rat models.

Scientists still argue. The honest answer is fleas, possibly

yours. In Florence, a writer named Boccaccio watched his city die around him. By some accounts, more than half the city.

He wrote that people breakfasted in the morning with their kinsfolk, and that same night, supped with their ancestors in the other world. Breakfast to grave, in one

day. He survived, and built the most famous eyewitness account of the plague into the opening of the Decameron. And the people whose job was to explain

it? England kept unusually good records. Roughly forty to fifty percent of its parish clergy died, the priests who stayed at the bedsides. Fewer than eighteen percent of bishops did.

The closer you stood to the dying, the more likely you joined them.

Nobody knew why. Medicine had no concept of bacteria, so the learned blamed corrupted air. Others blamed a comet, the devil, or

the wrath of God. Flagellants marched through Rhineland towns, whips cracking against their own backs, begging heaven for mercy.

Heaven did not answer. And in the panic, a lie spread: that Jews had poisoned the wells. The pope himself, Clement

the Sixth, called the lie a lie. He issued two bulls in thirteen forty-eight declaring the Jews innocent, pointing out they were dying of the plague like everyone else, ordering the clergy to protect them, and threatening

their attackers with condemnation. He was widely ignored.

Months later, the authorities of Strasbourg killed about two thousand Jews, by period accounts, one massacre among many across the German lands.

Thousands of survivors fled east to Poland. A pope publicly fact-checked a conspiracy theory in thirteen forty-eight, and it did not save them.

That is the low point. Every power in Europe had swung at this thing and missed.

But in one walled city on the Adriatic, somebody was about to land the first real punch. In thirteen seventy-seven, the city of Ragusa, modern

Dubrovnik, passed a law. Anyone arriving from a plague-affected place had to wait in isolation for thirty days before entering. They called it the trentino. No prayer, no potion, just a wall

made of time. And it worked well enough that Venice copied it and stretched it to forty days: the quarantena. Forty days. Every time you have

heard the word quarantine, in a pandemic, at an airport, you were speaking fourteenth-century Venetian. The first human victory over the plague was not

a cure. It was a calendar. And what about the plague doctor, the long black coat, the beaked mask? Almost everything you picture there is from the

wrong century. The beaked costume is credited to a French royal physician, Charles de Lorme, around sixteen nineteen, nearly three hundred years after the Black Death, for later outbreaks. The half-foot beak was packed

with theriac, a paste of more than fifty ingredients including opium, viper flesh, cinnamon, myrrh and honey, so the doctor could breathe perfumed air against the miasma. It could not stop a single flea bite.

De Lorme, physician to kings, lived to ninety-four, outliving legions of patients his era's medicine could not save. So the survivors had a waiting wall and a scented

mask. But by then, something bigger had already happened, the plague had quietly rewritten who held power in Europe.

Here is the flip. Before the plague, the laborer at the bottom of the pyramid was cheap, because there were always more.

After the plague, he was the scarcest resource on the continent. Fields stood ready. Harvests waited. Workshops sat idle. And suddenly the man with a scythe could name his price.

Wages rose sharply, and we know the workers were winning, because the winners' bosses panicked. In thirteen fifty-one, England passed

the Statute of Labourers: a law to freeze wages at pre-plague levels and force the able-bodied to work. Read that law backwards. Parliament does not outlaw a raise nobody is getting.

It proved very difficult to enforce, because supply and demand does not read statutes, an early case study economists still cite. The resentment

it brewed helped boil over, a generation later, into England's Peasants' Revolt, with rebellions in Paris and Florence in the same post-plague

wave. Lords competing for scarce workers found the old feudal obligations harder and harder to enforce; the plague helped weaken serfdom across Western

Europe. The Church's grip loosened too. The prayers had failed, the processions had failed, and everyone had watched the clergy die with everyone else, so people began to question. Even art changed.

In the decades after, painters filled walls with the Danse Macabre: skeletons leading popes, emperors, peasants and children, all to the same grave. The plague supercharged that death-art tradition, and its skeletons still dance

through your Halloween. The disease had beaten kings and popes. But it had accidentally armed the peasant. The most powerful losers in Europe lost ground; the weakest survivors gained it. The plague itself, though, was

not finished with us. It kept coming back for three hundred years. The Great Plague of London, in sixteen sixty-five, killed roughly one hundred thousand people by most estimates, about a quarter of the city, before

plague finally faded from Western Europe. Then, in eighteen ninety-four, in an outbreak in Hong Kong, a bacteriologist named Alexandre Yersin finally put the enemy under a microscope and isolated it.

The killer of perhaps two hundred million people across history now carries his name: Yersinia pestis. And here is the last twist in the family

tree. The strain from the medieval mass graves sits near the root of the modern species, most plague circulating in the world today descends from the Black Death's own lineage. Descent runs forward from thirteen forty-eight, not backward

from Justinian. The plague never went extinct.

One to two thousand people still catch it every year, about seven a year in the United States. But caught early, modern antibiotics cure it: survival around ninety-eight percent. What once erased a third of a continent now loses

to a course of pills. For six centuries, the fight was one-sided, it just took us that long to learn which side would win. The plague taught us quarantine,

handed the laborer his first raise, and left its name on our fears; we answered with a calendar, a microscope, and a cure.

And that, for me, is the uncomfortable half of the ending: we found a cure for the plague. We are still looking for one for the lie.

The plague reshaped England from below. But three centuries earlier, England was remade in a single afternoon, by an invasion fleet,

an arrow, and a king who wrote down everything he had taken, field by field, in one great book. That is the next episode:

the Norman Conquest. Subscribe so you don't miss it.