In 1968, Margaret O’Brien and her husband bought a run-down house near Dublin with the intention of renovating it and opening it as a center for the arts. What they may not have known is that the house they had bought next to the Killakee Estate was formerly used by the notorious Hell Fire Club and was widely thought to be haunted. According to Paranormal Encounters, the O’Briens had the men working on the renovation live in the house in order to complete the job more quickly, but soon the workmen were reporting eerie sounds coming across the estate grounds at night, most notably a growling like that of a wild animal. Deciding to inspect these claims herself, Mrs. O’Brien soon found herself face to face with an enormous black cat with glowing red eyes standing in her hallway. She said that it glowered at her with a hateful and menacing look but disappeared as quickly as it had appeared.

After a few more encounters with the spectral cat of Killakee House, Mrs. O’Brien called a local priest to perform an exorcism to drive out the ghostly cat-beast. Afterward, there were no sightings of the cat, the arts center was able to open, and guests were able to stay unharmed. That is, until a group of drunk actors decided to hold a séance, after which the cat, as they say, came back.

Welsh legend tells of an enormous black cat known as the Cath Palug, whose name is traditionally said to mean “Palug’s cat” but which might derive from a word meaning “clawing” or “scratching.” According to Jones’ Celtic Encyclopedia, Cath Palug was born from a giant white pig (normal cat stuff) and had as siblings a wolf and an eagle, all of whom were sources of terror for the British Isles. The pig’s owner saw the giant monster cat and threw it into the sea, where it swam ashore at Anglesey. In the Welsh poem “Pa Gur” (“What man?”), Cath Palug is said to have killed 180 warriors before it was (presumably) killed by Cai, aka Sir Kay, King Arthur’s jerky older foster brother. We have to say “presumably” killed, because the poem is fragmentary, and we never see what happens after Cai goes to Anglesey to kill lions and encounters a different kind of cat.

In French versions of the story, it’s Arthur himself who battles the Cath Palug, whose name is often rendered as “Chapalu” in French. In L’estoire de Merlin, Arthur faces the devil cat after it has terrorized the countryside. Arthur at last manages to kill the cat with his shield, but this isn’t the case in every version: Le Roman des Franceis says Arthur was killed not by Mordred but by the Cath Palug, who threw him into a bog.

Washington, DC, has played host to innumerable monumental events and personages and is, of course, replete with ghost legends. Besides the various ghosts said to haunt the White House — including no less a figure than Abraham Lincoln himself — the US Capitol building is said to host a number of spectral figures, including a wandering Civil War soldier and the ghost of John Quincy Adams. However, perhaps the most famous spirit from the nation’s capital isn’t a politician or even human: It’s the Demon Cat.

According to Atlas Obscura, sightings of the ghostly feline go back to at least the 19th century, when after the Civil War, a night watchman claimed to have been approached by a black cat that got larger and larger as it grew closer, until it was the size of a tiger. This monster cat knocked the guard down and disappeared into the ether. Legend states that the Demon Cat appears just before national tragedies, such as presidential assassinations. Other legends claim that those who witnessed the cat died of fright. Evidence of the cat’s existence includes paw prints embedded in concrete in the Small Senate Rotunda and the letters “DC” imprinted elsewhere. A cat that can grow to tiger size and disappear is frightening enough, but one that’s also literate is terrifying to think about.

Iceland has a number of fascinating customs when it comes to the celebration of Christmas. While other countries might expect to see Santa Claus or Father Christmas put goodies in their stockings and presents under their tree, kids in Iceland expect 13 trolls to come down from the lava fields and lick all their bowls or steal all their sausages before leaving some treats in their shoes. These are the Yule Lads, the 13 sons of the ogress Gryla, who can hear children misbehaving all the way up in her cave and wants nothing more than to put naughty children into her stew. But Gryla and her spoon-licking, candle-stealing, sausage-swiping sons aren’t all that lurk in the dark Christmas season: Gryla’s enormous, child-eating feline companion, the Yule Cat, is also on the prowl during the holiday season.

As Smithsonian Magazine explains, the Jólakötturinn, or Yule Cat, is an enormous cat bigger than a house, who sniffs around the town looking to gobble up anyone who didn’t receive new clothes for Christmas. Although most American children would view clothes as about the worst kind of gift to get, for Icelandic children, they’re a lifesaver. Having new clothes was a sign that a child had behaved and that their family had made sure to properly prepare for the winter season, and the threat of the Yule Cat serves as incentive to reinforce that behavior.

Perhaps because cats were so associated with pagan worship by civilizations such as ancient Egypt, Jewish folklore often relates cats to demons. In fact, in Sephardic folklore (that is, among Jews of Spanish and Portuguese descent), it is believed that Lilith, Adam’s first wife before Eve who was banished from Eden because she refused to submit to her husband, transformed into a demonic black cat called El Broosha. According to Cat’s Most Wanted, this demon cat prowled around looking for its favorite prey — newborn babies — and when it found them, it would suck their blood. As a result, it was a custom for mothers never to leave their babies alone until they were at least nine days old.

One story of this demonic cat tells of a nurse who has to leave a mother and baby alone for a moment, and when she returns, the mother tells her that she has just dreamed that a black cat snuck into her room and transformed first into a jar and then back into a cat when it heard another cat meow from outside. It then took the baby from its bed and threw it out the window to another cat waiting outside. The nurse realizes that this wasn’t a dream when she looks out the window and sees a black cat running away with the baby.