These days the weasel has a reputation as a sneaky, sleazy, untrustworthy beast, and in folklore and myth weasels have sometimes been thought of as unclean, even poisonous; but weasels also appear in tales from around the world as brave, fierce, and honourable.

In Roman myth, the poet Ovid tells the story of the weasel’s origin in his Metamorphoses. When the hero Hercules’ mother Alcmena was in labour, the jealous goddess Juno instructed the goddess of childbirth, Lucina, to sit outside the bedchamber with her legs crossed and her hands tightly clasped. Alcmena’s red-headed maid Galanthis tricked the goddess by announcing that Hercules had been born; astonished, Lucina leapt up, and at that moment the spell was broken and Alcmena gave birth at last. Galanthis laughed at the goddess, who, enraged, grabbed her by her red hair, flung her to the ground, and changed her into a weasel. Because she helped by telling a lie, she was cursed to bring forth her offspring through her mouth. This last bit of the story is meant to explain the mistaken belief that weasel were impregnated through the ear, and gave birth through their mouths. For the Greek philosopher Plutarch, this was a metaphor for knowledge, which goes in through the ear and comes out through the mouth.

In the Middle Ages, weasels were thought to be venomous. Gerald of Wales told the tale of a man who removed the young from a weasel’s nest; she retaliated by spitting poison into his son’s milk, but when he returned her stolen children, she knocked the milk over, saving the boy. A folktale with Indian, Arabic, and Russian versions reverses this story: a man or woman returns home to find his or her son missing and their pet weasel covered in blood. The pet is killed, but later the child is discovered alive - and the bloodied corpse of the snake the weasel slew, saving the boy.

The weasel is the mortal enemy of the basilisk and cockatrice - two poisonous reptilian monsters often conflated with each other in myth. The First Century natural historian Pliny the Elder said that just the smell of a weasel was enough to kill a basilisk. In the Middle Ages, encyclopedist Bartholomaeus Anglicus wrote that “the biting of the weasel is death to the cockatrice” (perhaps because the weasel was supposedly venomous too?) and described how men would put a weasel into a basilisk’s lair to fight and kill it. As long as the weasel had eaten the herb rue before the fight, it was safe from the basilisk’s poisonous breath. (Perhaps rue was the healing herb delivered by a grateful weasel in an Irish folktale to a man who was wounded helping the weasel dispatch a rat.)

The weasel’s reputation as a fierce little fighter sometimes makes it a hero, sometimes a villain. Heraldic coats of arms proudly bear the weasel and the ermine - a weasel in its winter coat, whose black and white fur also frequently appears. For the Blackfoot people of Alberta, Canada, the white fur was used to fringe a weaseltail suit, a garment which a warrior would carry into battle for its spiritual power, then wear when returning home victorious. On the other hand, the kama itachi, or “sickle weasel”, is a creature from Japanese myth - a tiny animal with sharp claws which flies in windstorms at night. It’s blamed for cold-chapped skin, sandals which break for no apparent reason - and is also a less embarrassing explanation for scratches received in the bedroom.

Sometimes, though, weasels appear in folktales as fools or dupes. The Mi’kmaq people of Canada and northern New England tell the story of two weasel sisters who playfully choose stars for their husbands - only to wake up to find themselves married, and worse, living in the world beyond the sky; trying to get home, they end up stuck at the top of a pine tree. One of Aesop’s fables tells the story of a bat caught by a weasel. The bat pleads for its life, but the weasel swears it’s the enemy of all birds. But I’m not a bird, says the bat, I’m a mouse! After this close shave, the bat is caught by a different weasel, who swears it’s the enemy of all mice. But I’m not a mouse, says the bat, I’m a bird! And once again the bat escapes with its life.

In a story from the Tillamook people of Oregon, a weasel appears as a trickster, part cunning and part foolish. His older brother, the panther, leaves him to tend the fire; instead he eats and plays, then steals embers from their neighbours, the wolves. When the wolf brothers complain, panther kills each of them in turn, until panther himself is killed, leaving the weasel without a meal ticket. He begins stealing food from humans, but finally gets his comeuppance when one of his victims lies in wait with a club!

So, in myth and folklore, the weasel can be everything from a monster to a fool - and, sometimes, a hero.