A few years before he died in 1261, the Inquisitor and Dominican friarStephen of Bourbon began writing a long treatise on faith—one that included one of the more perplexing incidents of human superstition that he had witnessed. Warning of the dangers of idolatry and superstition, Stephen related an incident that had taken place in the Dombes region of France, near Lyon: while hearing confession, many peasants told him that they had been carrying their children to the grave of Guinefort, a saint Stephen had never heard of before named—when he looked into the manner, he discovered that this supposed Saint Guinefort was, in fact, a greyhound.

The story, as Stephen relates, is as follows: In the diocese of Lyon, close to the village of the nuns called Villeneuve, on the estate of the lord of Villars-en-Dombe, there was a certain castle whose lord had a baby son from his wife. But when the lord and lady and the nurse too had left the house, leaving the child alone in his cradle, a very large snake entered the house and made for the child’s cradle. Guinefort dashed swiftly under the cradle in pursuit, knocking it over, and attacked the snake, answering bite with bite. The dog killed the snake and threw it far away from the child’s cradle, which was now covered in blood, snake and dog alike. When the nurse returned, she thought the child had been killed and eaten by the dog and so gave out an almighty scream. The child’s mother heard this, rushed in, thought the same and she too screamed. Then the knight similarly once he got there believed the same, and drawing his sword killed the dog. Only then did they approach the child and find him unharmed and sleeping sweetly.

The lord and his wife quickly discovered their fatal error, and ashamed and embarrassed by what they had done, they buried the Guinefort outside the castle walls. In due time, Stephen goes on, the castle was destroyed and the land left deserted. But the local peasants, “hearing of the dog’s noble deed and innocent death, began to visit the place and honor the dog as a martyr in quest of help for their sicknesses and other needs.”

The worship of a dog was perhaps bad enough, more blasphemous was that the locals had given him the name of a saint, making a mockery of the Church’s institutions. But far graver was what these peasants were doing in the name of this sainted dog: a woman with a sick child would take her or him to the spot in the woods where Guinefort’s body lay buried, and there she would leave her child, naked on a bed of straw, with candles burning on each side of the child’s head. The parent would not return until the candles had burned out, and, as Stephen was told, many children did not survive this ordeal of open flame and flammable straw: “Several people told us that while the candles were burning like this they burnt and killed several babies.” Other children, left defenseless in the forest, were instead devoured by wolves. If the child survived the night, the mother would then dunk it nine times in the river—only then, if the child was still alive, would she or he be pronounced cured.

Stephen was aghast at what he found in Dombes, and he used the story in his treatise to emphasize the folly and danger of superstition. But like many accounts from the Middle Ages, Stephen’s story of the cult of Saint Guinefort raises more questions than it answers. At the heart of this: how did a dog come to be recognized as a saint? And why were those who revered this saint leaving their children to die in his name?

Among the many things Stephen could have faulted these peasants, he might have started with unoriginality. For, as it turns out, the story of Saint Guinefort was not unique to Lyons, nor even to France. It is actually among the oldest and most durable folktales, which can be traced back a thousand years earlier, to India. There it is known as the “Brahmin and the Mongoose.” The story, as related in the ancient Indian text, the Panchatantra, tells of a Brahmin and his wife, who have a son and a mongoose. As with her human child, the mother “cared for the mongoose also like a son, giving him milk from her breast, and salves, and baths, and so on. But she did not trust the animal, for she thought: ‘A mongoose is a nasty kind of creature. He might hurt my boy.’” While she is out one day she tells the Brahmin to look after their son, but he soon too leaves to beg for alms, so that only the mongoose is there to protect the child when a black snake appears and approaches the cradle. The mongoose, “fearing for the life of his baby brother, fell upon the vicious serpent halfway, joined battle with him, tore him to bits, and tossed the pieces far and wide. Then, delighted with his own heroism, he ran, blood trickling from his mouth, to meet the mother, for he wished to show what he had done.” Proving that no good deed goes unpunished, the mother, when the mongoose approached, “saw his bloody mouth and his excitement, she feared that the villain must have eaten her baby boy, and without thinking twice, she angrily dropped the water-jar upon him, which killed him the moment that it struck.” By the time the Brahmin returns the wife has discovered her error, and bitterly laments the death of the pet loved as a child: “Greedy! Greedy!” she tells her husband. “Because you did not do as I told you, you must now taste the bitterness of a son’s death, the fruit of your own wickedness.”

Versions of this story have been found throughout India and southeast Asia, as well as China and Mongolia, among Jewish communities in Egypt, and throughout Europe from Russia to Wales (where it is known as the story ofLlewellyn and his hound Gelert). While the snake is the constant menace in the majority of these tales, the mongoose’s role is played by whichever pet is deemed most loyal: as the tale moves north through Europe and through time, the martyred defender changes from mongoose to wolf, and finally, to dog.

On its surface, the moral of this fable is clear: rash action leads to folly. But as ethnologist and folklorist Stuart Blackburn suggests, another way to make sense of the fable, particularly as it mutates throughout a series of different contexts, is to pay attention to the frame narrative in which it appears. In many of these frame narratives, particularly in India and Tamil, the problem with the family is that they have grown too close to the mongoose—alongside the danger of hasty decisions is the danger of growing too attached to one’s pets, treating an animal as though it was a child. In one Tamil version of the story, the mother mourns the dead pet as her “precious darling,” and in another he’s described as “their all-in-all—their younger son, their elder daughter-their elder son, their younger daughter, so fondly did they regard that little creature.” In most versions of the story, the animal is the “first-born son,” and the human child is seen as perhaps a reward to the couple for proving their ability to love their animal son. (As Blackburn notes, the Tamil language “leaves no doubt about this fictive affinity: a mongoose is….‘mongoose-child.’”)

But if the problem with these Southeast Asian couples was undue affection for their mongooses, by the time the story got to France, the relationship to the pet had changed considerably. For Guinefort is not a lowly mongoose, a creature viewed with suspicion, but a greyhound, and in medieval France, a greyhound was not just any pet and not just any dog. In the thirteenth century Vincent of Beauvais distinguished greyhounds from ordinary hunting and guard dogs; greyhounds, he claimed, are “the noblest, the most elegant, the swiftest, and the best at hunting.” Often incorporated into family crests, the greyhound, like the lion or the ermine, was an exemplum of nobility and chivalric ideals. And so in the story that Stephen relates, the crime is doubled: not only does the lord hastily kill Guinefort, but he disposes of the greyhound’s body in a particularly undignified manner (“[he] threw his body into a well in front of the castle gate, and placing over it a very large heap of stones they planted trees nearby as a memorial of the deed”). Having killed his noble pet in such an ignominious fashion, and having revealed himself to be anything but noble himself, it’s no wonder that the lord’s castle is subsequently obliterated—“by divine will.”

On hearing details of this blasphemous story, Stephen’s own punishment of these peasants was far less harsh. He claimed they were basically committing infanticide, leaving their children to die of exposure or wolf attack, and he understood them to be following the directions of a local witch. And while he had at his disposal all the powers of the Inquisition, he opted not to prosecute them for heresy or demand their executions. Instead, he saw them as victims of the serious but far lesser error of superstition: their actions were erroneous but not malicious, and while they may have been consulting witches they were not, in his estimation, themselves witches. While the devil and his minions might use magic to harm children, these women, Stephen saw, believed that they were trying to help their children. Their children, they believed, had become changelings.

As with the story of the faithful pet, the belief in changelings also expands well beyond France. When an infant became sick, or would not stop crying, or in any other way exhibited abnormal behavior, parents would sometimes become suspicious that their real child had been abducted by spirits, who had left in its place a spirit-child of their own. The women who left their babies at the shrine of Saint Guinefort were not abandoning their children to die; they were, they believed, taking a changeling within earshot of its spirit-parents, the fauns of the woods, who would hear their spirit-child crying, take pity on it, and replace it with the human child they’d originally abducted. A child who made it through this terrible ordeal was , they believed, simply the original child returned to the parents. As Stephen relates, mothers who took their children to the shrine of Guinefort would invoke “the demons to adjure the fauns in the wood of ‘Rimite’ to take the sick and failing child which they said belonged to them (the fauns) and return to them their own child big, plump, live and healthy.” The barbaric actions by the women of Dombe at the shrine of the dog saint may have been a means for a community to dispose of children who were ill or otherwise disabled—in a manner that was ritualized so as to absolve the individual parents of any guilt.

If Stephen was able to convince the local community not to leave their children to die in honor of Guinefort, the practice of turning to the dog for help in healing children would last well into the nineteenth century. Making the pilgrimage to the remnants of Saint Guinefort’s shrine, one would tie two branches together, in order to “knot” a child’s fever, or “unknot” a child’s legs if she or he was slow in learning to crawl or walk. To rid a child of fever the babies’ clothing might be left behind in the woods; an ethnologist following the pilgrimage route in 1879 saw “knotted branches by the thousands,” and a “mass of clothing,” suggesting that the shrine was still heavily frequented.

This kind of sympathetic magic was by no means unusual or infrequent, but nineteenth-century scholars and theologians who studied the area were still trying to figure out what it had to do with a noble greyhound who ended up a Catholic saint. Discussing the matter in 1886, Abbé Jean Delaigue of Lyons asked the central question: “Is this Guinefort a saint or is he a dog?” Delaigue comes to the conclusion that Guinefort was a real human saint, and that the local townsfolk had duped this inquisitive interloper with a tall tale. If the Dominican inquisitor had believed the story, Delaigue states, “one can only conclude that he was remarkably credulous and that people took advantage of his simplicity to laugh at his expense.” But even at that late date the matter was not settled; investigating the wooded region in 1879, the ethnologist Louis Augustin Vayyssière reported that “All those whom I approached told me that Saint Guinefort was a dog.”

It fell to the scholar Jean-Claude Schmitt, who put all the pieces together, finally, a century later. He traced the origins of the greyhound saint to a relatively obscure human saint named Guinefort, whose vita emerged sometime between the eighth and twelfth centuries. Schmitt diligently traced the spread of Guinefort’s cult from Pavia throughout Europe, including the many versions of his names, and the various similar-sounding saints who were mistaken for Guinefort and vice versa. Of the original Guinefort not much is known—his hagiography is so similar to that of Saint Sebastian, and woefully unreliable. (Like that more famous martyr, he was condemned to be shot “so full of arrows that he resembled a hedgehog”). Among the few salient details is that his feast day was August 22, and that he was known as a protector of sick children.

Guinefort’s feast day falls during the “dog days” of summer (July 24-August 24), the period in summer when the dog-star Sirius rose around the same time as sunrise, a time also believed to result in a higher incidence of rabies. Numerous other saints during the dog days are associated with dogs and depicted with them, including Saint Ulrich (feast day July 4; patron invoked against rabid dogs), Saint Roch (feast day August 16; patron of good dogs), and Saint Christopher, whose feast day on July 25 marked the start of the dog days—and who was sometimes depicted as having the head of a dog.

Guinefort the dog saint, Schmitt demonstrates, emerged from the confluence of three very different folk traditions that all involved protecting children and which merged in the woods outside Dombe. The fable of a loyal dog, protector of children; a ritual magic to rid children of spirits; and a saint whose life was sketchy and who was known only as a patron of children, were garbled together to form a holy greyhound on whose behalf peasants abandoned children in the woods.

The human saint Guinefort, it seems, was often enough depicted alongside dogs that his story became that of the loyal greyhound, in an odd form of mistranslation. Without a clear story of his own, Guinefort’s life became that of a durable folktale, even though it meant a transformation from human to canine. That this community could call a dog a saint is perhaps the strangest aspect of this, but as I’ve discussed in my book The Afterlives of the Saints, it is precisely in the lives of the saints—multitudinous, bizarre, permeable—that Catholicism is most susceptible to folk tradition. The stories of the saints are constantly being adapted to the needs of specific communities, abandoning orthodoxy as necessary, often to the chagrin of the Vatican—be it the current cult of Santa Muerte in Latin America, or the thirteenth-century veneration of a dog.

Stephen the Inquisitor, defender of the faith and orthodoxy, was in no position to appreciate this, and moved decisively to end the cult once and for all. “We then had the dead dog dug up and the grove of trees cut down and burned along with the dog’s bones,” he concludes. “Then we had an edict enacted by the lords of the land threatening the spoliation and fining of any people who gathered there for such a purpose in future.”

In his narrative of these events in Lyons, you can read something like a three-act tragedy on the topic of power in the Middle Ages. At first is an all-powerful lord, but one who does not act with the morals and nobility befitting his station, rushing to judgment and then failing to properly bury a noble animal—who as a result of his immorality is punished, his kingdom destroyed. In his wake another source of authority springs up: the folk-saint Guinefort, who heals through magic and works to address the needs of the people in a manner far more intimate than orthodox dogma could. He too, is destroyed, this time by the Church, a third source of power which roots out heresy and superstition in an attempt to restore order. While we sometimes think of the power dynamics in the Middle Ages as hegemonic, with the peasants perennially oppressed by both Lord and Bishop, the story of Guinefort may in fact represent one example of how that power was constantly shifting.

And if Stephen thought he got the last word, that he definitively destroyed this wrong-headed folk-belief once and for all, it’s worth remembering that the cult of Guinefort, protector of children, not only outlasted Stephen and the Inquisition, but also the dominance that the Church held over Europe until the Modern Age. In the late 1960s, when the Vatican revolutionized itself to stay current and relevant, Jean-Claude Schmitt was still making inquiries about Guinefort in the regions around Lyon—asking around about a supposed healer in the nearby forest, one of the locals answered Schmitt, “My grandmother told me: it seems he was a dog!”