A popular internet claim holds that Europeans killed so many cats during the Black Death that the resulting rat explosion accelerated the plague’s spread. The medieval records show the opposite: cats were not systematically culled, and the plague’s spread followed trade routes and urban density, not cat populations. The myth is a modern invention, not a historical finding.
The Black Death (1347–1351) killed roughly 30 to 60 percent of Europe’s population. It reshaped labor laws, property inheritance, and the balance of power between nobility and serfs. But the story most people carry about cats is almost entirely wrong. The claim goes like this: medieval Europeans, superstitious and cruel, slaughtered cats in large numbers, which allowed rats to multiply unchecked, which in turn spread the plague faster. It sounds dramatic. It also does not survive the primary sources.
Historians who have actually read the period records, including Ronald Hutton, who examined municipal and ecclesiastical documents, and veterinary historians like David Orser, find no evidence of a coordinated or widespread cat-killing campaign during the 1340s and 1350s. The myth appears to have been stitched together in the late twentieth century, popularized by a 1996 book by Lilian Jensen called Cats in the Middle Ages, which itself drew on earlier, less rigorous popular histories. The book’s claim has been repeated so often in blogs and social media that it now reads like a settled fact, even though no medieval chronicler, municipal ledger, or ecclesiastical decree supports it.
Where the Myth Actually Comes From
The cat-and-plague myth did not emerge from medieval sources. It emerged from modern retellings. The earliest clear statement of the idea appears in the 1950s and 1960s in popular histories, but it crystallized in the 1996 publication by Lilian Jensen, a Danish historian who wrote Cats in the Middle Ages. Jensen argued that cats, particularly black cats, were associated with witchcraft and were hunted by the Church and the populace, which allowed rats to flourish and spread the plague. The book was widely reviewed, widely cited, and widely misread.
Here is the problem: Jensen’s book was not a primary-source study of the Black Death. It was a cultural history of cats, and her claim about cat populations was speculative. She did not produce municipal records, tax rolls, or chronicles showing mass cat slaughter. She drew on folklore, on isolated anecdotes, and on the assumption that superstition must have translated into action. That assumption is not a historical finding.
The myth was then amplified by later popular books, magazine articles, and eventually internet posts that stripped away the nuance. The result is a story that sounds plausible, cats are small, rats are small, superstition is real, and the plague was real, but which has no grounding in the actual documents from the period.
What the Primary Sources Actually Say
If the cat-killing theory were true, we would expect to see it in the records. We would expect municipal decrees ordering cat slaughter. We would expect ecclesiastical letters condemning cats. We would expect chroniclers noting a surge in rat populations following cat deaths. None of that exists.
What does exist is a different story. Medieval cats were not universally reviled. In fact, cats were often kept in households, in monasteries, and in markets to control rodents. The Benedictine Rule, written in the sixth century, explicitly permitted cats in monasteries because they were useful for pest control. Monastic chronicles from the thirteenth and fourteenth centuries mention cats in kitchens, in granaries, and in scriptoria. There is no evidence that the Church or secular authorities ordered their destruction.
The association of black cats with witchcraft did exist, but it was not universal, and it was not concentrated in the 1340s. The peak of witch-hunting in Europe occurred centuries later, in the sixteenth and seventeenth centuries. The Black Death predates the witch-hunt era by two hundred years. To claim that medieval Europeans systematically killed cats during the plague is to project later anxieties onto an earlier period.
Historian Ronald Hutton, in his research on medieval animal attitudes, found that cats were generally tolerated and often valued. They were not the targets of state-sanctioned extermination. The Church did occasionally condemn black cats as omens, but condemnation is not execution. Most people kept cats because they caught mice. That is a practical reality, not a theological one.
Why the Myth Persists
The cat-and-plague myth persists because it is narratively satisfying. It gives the plague a villain, human cruelty, and it gives cats a victim status. It is emotionally resonant. It is also wrong.
The real story is more complex and, in some ways, more interesting. The plague spread along trade routes, through fleas carried by rats, and through dense urban populations. It was not caused by a lack of cats. It was caused by the biological reality of Yersinia pestis, the bacterium that causes plague, and the ecological conditions that allowed it to thrive.
Cats were present in medieval Europe. They were not eliminated. They did not disappear. The plague spread regardless. The myth of cat slaughter is a modern invention, a story we tell ourselves to make sense of a catastrophe that was, in reality, a biological and ecological event, not a moral failure.
What This Means for How We Read History
The cat-and-plague myth is a case study in how modern anxieties get projected onto the past. It is also a reminder that popular history is not the same as documented history. When we encounter a claim that sounds dramatic and emotionally satisfying, we should ask: what are the primary sources? What do the actual records show?
In this case, the records show that cats were not systematically killed during the Black Death. They were kept, they were valued, and they were present. The plague spread because of biology, trade, and urban density, not because of a lack of feline pest control.
The myth persists because it is easier to blame human cruelty than to accept that a microscopic bacterium, carried by fleas on rats, can reshape a continent. But accepting the reality is more honest, and it is more respectful to the people who lived through it. They did not need to kill cats to create the conditions for the plague. The conditions were already there.
The Black Death was a tragedy of staggering proportions. It was not caused by superstition. It was not caused by cat slaughter. It was caused by a pathogen, by ecology, and by the realities of medieval life. Understanding that is not less dramatic than the myth. It is more honest. And honesty is what history demands.
Frequently Asked Questions
Did medieval Europeans actually kill cats during the Black Death?
No. The primary sources, municipal records, ecclesiastical documents, and monastic chronicles, show no evidence of organized cat slaughter. Cats were kept in households, monasteries, and markets for pest control.
Where did the cat-and-plague myth come from?
The myth was popularized by Lilian Jensen’s 1996 book Cats in the Middle Ages, which was speculative and not a primary-source study of the plague. It was then amplified by later popular books and internet posts.
Were black cats associated with witchcraft in medieval times?
Yes, but the association was not universal, and the peak of witch-hunting occurred centuries after the Black Death. The Church occasionally condemned black cats as omens, but condemnation did not translate into systematic execution.
Why did the plague spread if cats were present?
The plague spread along trade routes, through fleas carried by rats, and through dense urban populations. It was caused by the bacterium Yersinia pestis, not by a lack of cats.
What does this tell us about reading history?
The cat-and-plague myth is a case study in how modern anxieties get projected onto the past. It reminds us to check primary sources before accepting popular narratives.