Crocks of gold guarded by cats and other supernatural entities are legion in Ireland and may be linked with treasures reputedly buried at crossroads as an offering to Hecate, goddess of the underworld, and the belief that cats were assigned to guard the treasure. Another Celtic myth tells that the cat, Hecate's companion, became her consort and subsequent "King of the Cats". This title did the cat no favours when later; with the arrival of Christianity, little time was lost in identifying the cat with the devil.
Cat-Kings in Ireland were considered to be faerie beings, and rituals of the Cat-King cult took place in burial mounds and caves. Traditionally, caves were thought to be entrances to the underworld, and burial mounds antechambers to that forbidding place. The burial mounds were said to have been built by the "Danaans, "the people of the goddess Dana", whose power is believed to have been broken when the ancestors of the modern Irish arrived around 1000 BCE. The Danaans were thought to have become reduced in size and then, with their goddess, retired underground to inhabit the mounds as "faerie folk".
In Ireland it is considered bad luck to take a cat when one moves from one house to another. When a visitor enters a house it is the custom to say "God bless all except the cat," to show their distrust and dislike for the "evil creatures" whom it was believed had powers over life and death.
A cat which had just washed its face was not to be glanced at, for the person to do so was doomed to die. When a family moved to a new house they would not let a cat enter it for one year as they believed this would bring bad luck.
In Irish legend the folk hero "Finn mac Cumhail" was held captive by "Cormac mac Art," the King of Erin, who promised to free his prisoner only if a male and female of every species of animal were brought to him in the ancient city of Tara. The list included a pair of cats from the cave of Cruachain.
Hecate's Legacy: The Greek goddess Hecate, who had once adopted the shape of a cat when threatened by the giant Typhon, thereafter had a special affection for cats. She became the patron saint, so to speak, of witches, as Shakespeare knew when he made his "dark and midnight hags" appeal to her for help in bringing about the ruin of Macbeth. And so it naturally followed that those who practised witchcraft should also cultivate a liking for cats!