Category Archives: Medieval

The Black Death: Four Things You May Not Have Known

plague victims 'La Franceschina black death bubonic plague

This image of plague victims comes from ‘La Franceschina,’ a fourteenth-century manuscript.

The fourteenth-century plague was one of the most catastrophic pandemics in human history. In a six-month span, bubonic plague wiped out sixty percent of London’s population. Some historians estimate that it killed upwards of twenty million people within five years and by the end of the fourteenth-century, the disease—along with a famine from earlier in the century—cut Europe’s population in half. But current research proves we have some major misconceptions about the disease. I’ve combined this new information with some little-known facts, shedding light on four things most people don’t know about the Black Death.

  1. Tartars Used the Plague as a Biological Weapon

While some researchers believe the fourteenth-century Black Death was spread via Silk Road trade, that’s not how it spread to Kaffa. We can blame a Tartar attack on the port in 1343 for that. (Tartars were Islamic converts and descendents of the Mongols living in the western part of their empire.) During the mid-fourteenth century, Tartars controlled Crimea, so when a dispute between locals and Italians in the town of Tana resulted in the death of a Muslim man, the Tartars intended to capture and kill the Italians who then escaped to Kaffa. When Kaffa refused to give up the Italians and barred the Tartars entry into the city, a sieged ensued…and lasted for three years.

Siege Baghdad 1258 mongols

While this isn’t the Siege of Kaffa, this illustration of the Conquest of Baghdad by the Mongols in 1258 from Rashid-ad-Din’s Gami’ at-tawarih illustrates what Kaffa’s siege might have looked like.

A historical account written sometime between 1348 and 1349 by Gabriele de’ Mussi—a notary from north of Genoa—describes the horrific events of the third year of the siege.

… the whole army was affected by a disease which overran the Tartars and killed thousands upon thousands every day… Tartars died as soon as the signs of disease appeared on their bodies: swellings in the armpit or groin…”

“The dying Tartars… ordered corpses to be placed in catapults and lobbed into the city…. What seemed like mountains of dead were thrown into the city, and the Christians could not hide or flee or escape from them, although they dumped as many of the bodies as they could in the sea. And soon the rotting corpses tainted the air and poisoned the water supply…”

That’s right. The Tartars catapulted corpses into the city of Kaffa, turning their dead soldiers into biological weapons.

Though it seems he didn’t directly witness the siege, most consider de’Mussi’s account accurate. While some historians believed the biological warfare caused the spread of plague through Western Europe, current research suggests the two occurred independent of one another.

  1. Most Plague Victims Weren’t Infected by Flea Bites

Most people will remember learning in school that fleas on rats transmitted the plague to victims. After a flea bite, the Yersinia pestis bacteria infected each person, symptoms ensued, and most people died. The end.

Current research proves that’s not entirely true.

When construction workers tunneling beneath London’s Charterhouse Square stumbled upon twenty-five skeletons, the long-trusted theory changed. Researchers believed the site—an unexcavated area once home to a medieval monastery—contained a Black Death cemetery.  DNA extraction and analysis confirmed  twelve of the victims had been exposed to and later died of the plague. Scientists compared the medieval strain of the bacteria to the strain that killed sixty people in Madagascar in 2011 and found their genetic codes were identical.

plague pits

This illustration of medieval plague pits shows how the twenty-five corpses found in London might have been buried.

According to the World Health Organization, fleas on rats carried the Madagascar strain, but once the infection spread to the victims’ lungs, the bacteria could be transmitted via the air. This led researchers to conclude that—for the most part—coughing and sneezing transmitted the disease to medieval victims, not fleas.

To me, the air-born theory makes far more sense than the flea-bite theory, especially when considering that the disease killed sixty percent of London’s population in six months.  I suppose it’s possible—perhaps even likely—that six out of ten Londoners were bitten by fleas during that six-month period, but it seems even more likely that they were exposed to a cough or sneeze. A study of wills from the time shows relatives dying within hours of one another, which I think suggests the bacteria was spread from human to human.

I suppose none of really that matters anymore since the DNA analysis and comparison with the Madagascar strain proves the plague was air born.

  1. Fleas Might Have Been Infected By Gerbils, Not Black Rats
great gerbil bubonic plague nils stenseth

Researcher Nils Stenseth believes great gerbils from central Asia are responsible for spreading bubonic plague.

A new study from the University of Oslo suggests the pesky fleas who started the Great Plague were  infected and transported by gerbils, not black rats. How on Earth did they figure this out? With climate data. By scouring tree ring records which coincided with 7,000 historical incidences of plague, researcher Nils Stenseth found that tree rings from Europe showed no consistent weather patterns. But, Asian tree rings did. While the wet springs and warm summers experienced in Central Asia before each outbreak weren’t suitable for  black rats, they were ideal for great gerbils.

According to Stenseth in an interview with, his research shows “that wherever there were good conditions for gerbils and fleas in central Asia, some years later the bacteria shows up in harbor cities in Europe and then spreads across the continent.”

And since we now know—thanks to the twenty-five skeletons found in London—that the bubonic plague bacteria has hardly changed over time, it makes sense that resurgences of plague are caused by an increase in gerbil population rather than by new strains, further supporting Stenseth’s theory.

map black death plague

This map by Encyclopedia Britannica shows the spread of the Black Death through medieval Europe.

  1. Cat Massacres Didn’t Lead to an Increase in the Rodent Population and Plague
pope gregory ix

Pope Gregory IX has some strange ideas about what heretics did with black cats.

As I was combing the internet, I found a variety of uncited rumors about the thirteenth-century massacring of cats. Supposedly, in 1233 Pope Gregory IX issued a papal bull called “Vox in Rama.” The bull discusses the rather strange use of black cats in satanic and heretical rites. In his book, Witchcraft in the Middle Ages, Jeffrey Burton Russell describes the strange ritual.

The heretics…have secret meetings. When a postulant wishes to become a member of their congregation, he is led into the midst of the meeting, whereupon the Devil appears in the form of a toad, goose, or duck, as a black cat with erect tail which descends a statue backwards to meet his worshipers…  The postulant kisses the apparition either on the mouth or on the anus.

The bull also suggests heretics participated in other rituals in which they  kissed the anus of a black cat. You can read more about that here.

Despite Pope Gregory’s published opinion, I can find no evidence of people massacring cats as a result. So why is that? Probably because most people living in the 1200s wouldn’t have been aware of his opinion. It wasn’t like they could walk to the local library and pick up a copy of the bull for a nightly read. Besides, it wasn’t intended for the average person. It was intended to help bishops interrogate and root out heretics, like the Cathars.

But, for a moment, let’s ignore a lack of archeological and written evidence and say thirteenth-century people did massacre cats. The bull was issued over a century before the Black Death gripped Europe and if killing cats was a passing fancy, the feline population might have been able to bounce back by the time plague struck and kill a number of the pesky rats…or gerbils. Not that that would matter really. The plague was air born, remember?

Now this is not to say medieval people had a fondness for cats. In her article, “Heretical Cats: Animal Symbolism in Religious Discourse,” Irina Metzer discusses the general mistrust of cats during the Middle Ages. While people tolerated cats because they killed rodents, people viewed felines as “incompletely domesticated” and unwilling to serve humans when there was an expectation that God put animals on the Earth for that purpose. Primary documents show us some unfavorable conclusion about cats. People compared them to heretics, the devil, and witches.

**I want to thank my dear friend Marco for helping me with the research for this article.

profile picAndrea Cefalo is a Medieval fiction author and history blogger. Her debut novel The Fairytale Keeper, was a quarter-finalist in Amazon’s 2013 Breakthrough Novel Contest. The sequel–The Countess’s Captive—was published earlier this year.  She is currently working on the third book in her series.

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Inventing the Penny: Charlemagne’s Lost Effort at a Standard Currency

Andrea CefaloAndrea Cefalo is a Medieval fiction author and Medieval history blogger. Her debut novel, The Fairytale Keeper,  was a quarter-finalist in Amazon’s 2013 Breakthrough Novel Contest. The second book in The Fairytale Keeper series–The Countess’s Captive-debuted earlier this year.  She regularly posts about Medieval history on Facebook and Twitter.

Charlemagne and the Silver Penny


Charlemagne simplified the currency of Medieval Europe in the ninth century.

For certain, easing the trade of goods and services is the truest purpose of standard currency. When Charlemagne declared that 240 pennies should be minted from a pound of silver, he eased the trade of goods and services throughout the Holy Roman Empire. For the next 400 years, the penny was made from real silver just as Charlemagne had ordered. Therefore, it had a standard value. The penny might have been called different things in different areas—the  French denier, the German pfennig, the Spanish dinero, the Italian denari—but each coin had  the same silver content, and the same value.

Because of Charlemagne’s efforts, an English wool merchant could sell his wool to a weaver in Flanders who could sell his woven wool to a dyer in Cologne who could sell his died fabric to a merchant in Venice who could sell his wares to a fashionable noblewomen with ease. None of them would have to worry about the value of the coins they traded. It’s similar to what the Euro does for Europe today.

Diluting the Penny

English Penny from the twelfth century featuring King John.

This English penny from the twelfth century features King John.

Throughout the twelfth and thirteenth centuries kings, noblemen, minters, and counterfeiters diluted the penny with some dire consequences and disastrous results.

During the reign of English King Henry I, the percentage of silver in coins plummeted. As punishment for minting low-quality coins, each mint master had his right hand cut off on Christmas day in 1124 at the Assize of Winchester. The threat of mutilation wasn’t enough to keep moneyers’ honest, and the improvement in coin purity was only temporary.

Reducing the silver content in coins was not a practice exclusive to England. In fact, records suggest it was worse in other parts of the Holy Roman Empire, especially the German lands.  According to Medieval Denominations, by 1100 the standard German pfennig had twenty-five percent less silver than it did in the days of Charlemagne—dropping its value to three-quarters of an English penny.

Medieval Pfennig

This thirteenth-century German pfennig minted in Cologne bears the likeness of the archbishop, not the king.

By 1299, the problems presented by diluted coins were so prevalent that England forbid their import. Maurice Powicke states in his book, The Thirteenth Century, that King Henry III  tried to rid England  of “the false and debase…coins which had been brought into England and Ireland from German and Rheinish ports.”

As I survey the twelfth and thirteenth-century German coins at Fitz Museum, I can see that the minting of Rheinish coins was not nearly as regulated as it was in England. In the German lands, many dukes, lords, counts, bishops, archbishops, as well as the emperor, had minting rights.  Germans—whether counterfeiters, dishonest minters, or greedy noblemen, I can’t be sure—blended baser metals, such as copper, into the coins.  People called the debased currency black money.  In some cases, coins had less than one percent of the silver than they should have.  Not surprising, merchants from across Europe preferred coins with a high silver content, such as the groschen.

Clipping and Shrinking the Penny

Edward I

Edward I blamed Jews for clipping coins.

Besides decreasing the silver content of coins, minters devalued their coins through the process of clipping. Despite the threat of mutilation and execution, clippers trimmed the edges of the coins, collected the fragments, and made a profit, all while passing off the coins as having the same value as unclipped coins.  In 1277, Edward I hanged Jewish merchants for clipping coins.

As well as clipping and reducing the silver content in coins, minters also reduced the mass. When King Stephen I depleted the treasury in 1140, he ordered the penny’s weight to be reduced so he could pay his military expenses in wars against his niece, Matilda.  English barons also began issuing their own coins. Large amounts of counterfeit and low-quality coins drastically reduced the value of the penny. During the time of Charlemagne, a shilling was worth twenty pennies. During Stephen’s reign, the shilling’s value dropped to twelve pennies, nearly decreasing the currency value by half.

Just as a bad king can debase a currency, a good king can improve it.  In 1182,  Henry II, demanded silver content in pennies be high and consistent. One hundred thirty years later, during the reign of Henry III, the first recorded public assessment of a coin’s purity was performed. It was called Trial of the Pyx and is still performed in Great Britain to this day.

Diversity in Coins


Gold coins, like the noble, made an appearance in the 13th and 14th centuries and quickly spread through Europe.

As political and economic systems became more complex, so did the coinage. During the high middle ages, the diversity in coins skyrocketed. Because the coins varied in silver content and size, they aren’t as easily comparable as the penny, pfennig, and denier of the ninth century. Trying to compare the values is a daunting task that I tried, but probably won’t continue. I can imagine what a burden this must have been for merchants and those in charge of accounts.


“Banks and Money.” Currency and Banking in the Late Middle Ages. N.p., n.d. Web. 23 Oct. 2014.

Brooke, Christopher Nugent Lawrence. Europe in the Central Middle Ages: 962-1154. Harlow: Longman, 2000. Print.

“Medieval Coin Denominations of Europe.” Medieval Coin Denominations of Europe. N.p., n.d. Web. 23 Oct. 2014.

“Medieval Sourcebook: William of Malmesbury: Counterfeit Money in the Time of King Stephen, 1140.” Internet History Sourcebooks Project. N.p., n.d. Web. 23 Oct. 2014.

Mortimer, Ian. The Time Traveler’s Guide to Medieval England: A Handbook for Visitors to the Fourteenth Century. New York: Simon & Schuster, 2011. Print.

“The Fitzwilliam Museum : Coins and Medals Home.” The Fitzwilliam Museum News. N.p., n.d. Web. 23 Oct. 2014.