Pronounced like “cat-shee” the name is derived from the Gaelic words “cait” meaning cat and “sith” the term for fairies. The malevolent ghost-like cat has all black fur aside from a small white spot on its chest and supposedly haunts the Scottish Highlands. The size of the creature is said to be close to the size of a large dog so many sightings could’ve mistaken a slightly larger animal with the Cat Sìth.
One of the theories about the Cat Sìth suggest that they aren’t fairies but are actually witches that have the ability to transform back and forth between human form and cat form. This however could only be done 9 times with the final transformation into the cat being permanent. This is often referenced as the origin for the concept of cats having 9 lives.
But why were the Cat Sìth considered malevolent creatures/spirits? Those in the Highlands did not trust them and believed that they were soul thieves. The common belief was that the Cat Sìth could pass over the corpse of the dead prior to burial and steal the soul from someone before the gods had claimed it. Special watches were set up to guard the dead known as “Feill Fadalach” which means late wake. Those on this watch would attempt to keep the Cat Sìth away from the room containing the corpse by distracting it in a variety of methods such as using catnip, riddles, games and music. The Cat Sìth was believed to be fond of warmth and therefore fires were never lit near the bodies so that they were not attracted to the area.
The Cù-Sìth is a spectral hound from Scottish folklore that haunts the Scottish Highlands, its name essentially means Fairy Dog. The creature is said to almost be the size of a bull with dark green shaggy fur and a coiled or braided tail – a very intimidating creature to see while roaming the moors of the Highlands! It was believed that they made their homes in rocky crevices and many accounts recall seeing glowing eyes in the shadows.
The Cù-Sìth was feared due to the belief that it was a harbinger of death – much like the Grim Reaper. So while the Cat Sìth would steal the souls of the dead, the Cù-Sìth would take the soul to the afterlife. Although mostly a silent hunter the Cù-Sìth would sometimes let out three blood-curdling howls that could be heard for miles around. Those that heard the howls would need to reach a place of safety before the third howl or they would be overcome with fear and die from sheer terror. Women who were nursing children were locked up as quickly as possible so that they would not be taken by the Cù-Sìth to a fairy mound where they would be forced to provide milk for the Daoine Sìth. The Daoine Sìth were “the people of the mounds” - a supernatural race, believed to be gods or spirits of nature that lived underground in fairy mounds. Many believed that beneath these mounds were the entrances to a parallel universe where they live that exists alongside the human world.
Similar creatues have appeared in popular culture. Although much more similar to the Irish Cú Sídhe which is a large black dog with shaggy hair – The Grim from the Harry Potter series seems to be inspired by these folklore tales. J.K Rowling took a lot of inspiration from Scottish locations and folklore for Harry Potter and it seems to be the case here too. The Grim, first appearing in The Prisoner of Azkaban, was also an omen of death and Harry had multiple encounters with it throughout the book with many of his friends and teachers being concerned with it signalling his death.