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Features

Murder by Poison: A Crime from 15th century Valencia

by Medievalists.net
March 1, 2020

By Danièle Cybulskie

In many depictions of the Middle Ages, murderers are not shy about spilling the blood of their enemies in the most brutal fashion, but in the real Middle Ages, many murderers were a little more concerned about not getting caught and forfeiting their own lives in the process. As a result, not every killing was as public and brutal as the famous murder in the cathedral. Instead, some killers used one of the most famous tried-and-true means for ridding themselves of their enemies, popular with murderers from ancient times to the villains of Agatha Christie: arsenic.

Carmel Ferragud’s article, “A Multiple Poisoning in the City of Valencia: Sanxo Calbó’s Crime (1442)”, tells the story of Sanxo Calbó, a long-unemployed textile worker, who used arsenic to kill his daughter Isabel and her grandmother, while making his son-in-law Pere Roquer, Roquer’s mother, Isabel and Roquer’s baby, and the housemaid all viciously ill. Calbó’s murders were not quick or bloody. He relied, instead, on the fact that his weapon of choice was both easy to obtain, and all-too-easy to administer.

In medieval Europe, arsenic was stocked as a matter of course along with other medicines. As with other medicines, the poisonous nature of arsenic is a matter of dosage and administration. While much less harmful if used topically, it is extremely deadly when ingested. According to Ferragud, arsenic “was used in a variety of ways and in different prescriptions for its healing properties, especially as a corrosive for treating the wounds of people and animals.” But like nightshade and monkshood, the poisonous nature of arsenic was well known to people in addition to its medicinal qualities. It was actively sold not just as a medicine, but as a poison, too: for killing rats.

Because of its medicinal uses, arsenic was most often sold at the apothecary shop. Apothecaries, with their many years of training and apprenticeship, could be trusted to measure out the correct dosages of such poisons in order to prevent accidental overdose. Still, the fact that arsenic is virtually undetectable made people nervous, and the authorities tried to establish regulations in order to control its sale. Ferragud says,

At the beginning of the fourteenth century, the municipal government of Barcelona refused to let apothecaries and their assistants sell realgar [red arsenic]. Only doctors of renowned prestige (bons e coneguts) could act as vendors of the substance, and they could only possess it if they swore that they would use it for medicinal purposes.

Authorities in Valencia as elsewhere also required that anyone who sold arsenic take note of the person who bought it. Jews in Valencia, Ferragud writes, “were not allowed to either buy or sell it. If they did, the fine rose to the remarkable sum of 1,000 sous, and if a convicted Jew could not pay it, he lost a hand.” The control of Jews’ handling of arsenic was no doubt related to a pervasive antisemitic belief that Jews would use it to poison Christians. This was a common and extremely damaging falsehood that led to vicious persecution during the Black Death, when Jews were accused of causing the pestilence by poisoning town wells.

16th century drawing of Valencia by Anton van den Wyngaerde

Because arsenic could be obtained for the (relatively) innocent purpose of ridding a household of rats, however, it wasn’t all that hard for a murderer like Calbó to get his hands on it. In Calbó’s case, all of Valencia’s safeguards fell short, as he managed to visit two shops within days to both purchase arsenic and then to return to complain about the poor quality and ask for stronger stuff – for killing rats, of course.

Calbó mixed arsenic into candy, which he gave to his daughter and her grandmother; then, he dosed their wine and even poured arsenic into the family well, so that every drink they took to rehydrate made them more ill. He laced the medicine Isabel was given to cure her illness, claiming he was sweetening it with sugar, but he was spotted by the housemaid, who had become suspicious after being poisoned herself. When Calbó was caught, he confessed (under torture) “to putting arsenic into the [medicinal] syrup, in the salt cellar, in the broth, in a pot and in the sweets”. Appalled, the city of Valencia decided to make an example of him. As Ferragud says,

Poisoning – a horrifying, abominable crime perpetrated insidiously and secretly, which gave the unwary victim no chance to defend himself or herself – was considered the greatest of all crimes, the greatest of all betrayals, and it had to be punished in the most terrifying way.

Calbó’s method of execution was indeed terrifying, purposefully made even worse because of the nature of his crimes. Ferragud explains,

According to the Valencian laws (furs), when someone killed a close relative, he or she was sentenced to death, by being buried alive under the body of the person who was murdered until they themselves died. However, it seems that the punishment was not carried out exactly in this way since Calbó was sentenced to be buried beneath his daughter and then, after being disinterred while still alive, to be hanged until he was dead.

For a criminal who had used a method of killing normally chosen for its subtlety, Sanxo Calbó’s own death was astonishingly public, and it’s not very hard to see why Valencians would want to deter anyone from committing such crimes. The sheer number and variety of ways in which he managed to administer the arsenic, as well as the fact that he was able to poison an entire household with a household product makes it easy to see why arsenic was, in Ferragud’s words, “the most feared poison during the Middle Ages.”

For much more on Sanxo Calbó’s poisonings, his motive, and witness testimony, check out Carmel Ferragud’s fascinating article “A Multiple Poisoning in the City of Valencia: Sanxo Calbó’s Crime (1442)” in its entirety. You can find it, along with many other fascinating tales of crime and punishment in Medieval and Early Modern Murder.

You can follow Danièle Cybulskie on Twitter @5MinMedievalist

Click here to read more articles from the Five-Minute Medievalist

Top Image: A 13th century glass panel showing a woman carrying a poisoned flask. Image courtesy The Metropolitan Museum of Art

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TagsCrime in the Middle Ages • Danièle Cybulskie • Medieval Social History • Medieval Spain • Medieval Violence

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