The Glaistig was a solitary supernatural being of the Scottish Highlands, with the upper half of a woman and the lower half of a goat, although she was also believed to appear in human and animal form. Her skin was grey, and long golden hair fell about her body. Like many of the fairy races she was often seen clothed in green, in the form of a long flowing robe, which covered her goat half.
She frequented the lonely lochs and rivers in the Highlands of Scotland, and is sometimes describes as a half earth, half water sprite, although in Gaelic her name means literally ‘water imp’.
In the diverse and changing traditions of the Highlands, the Glaistig was seen as both benevolent and malevolent towards humans. In one aspect she even takes the role of the Banshee, wailing at the death of important people. She was also thought of as a trickster – throwing stones and leading travellers astray from their paths. In her gentler role she was seen as a mischievous friend to children, and in older stories she was even trusted to play with children while their mothers were milking the cows. The Glaistig was also closely linked to cattle, and in some forms is seen as a herder of domestic cattle, and of wild deer.
Libations of milk were poured for her, especially on selected stones; this veneration may be linked with older fertility customs. The following story has the offering of milk being placed on a holed stone (often regarded as sacred in their own right) and it is easy to speculate that the Glaistig’s roots are as a goddess worshiped as a guardian of the cattle – and or the fertility of the herd.
In the village of Ach-na-Creige on the Isle of Mull, a Glaistig served as the guardian of the local cattle. It was customary to pour some milk into a holed stone on the cattle fold as a libation to the Glaistig. This small token was the only payment she requested for her long vigils. A local herds boy – who was widely known for his mischief – decided he was going to have some fun at the Glaistig’s expense, and poured boiling milk into the holed stone. The Glaistig severely scalded her tongue, and was so angry that she left the local countryside, and her wardenship of the village cattle for good.
There are many more traditions and stories about the Glaistig in existence, these can be found in The Fairy Tradition in Britain by Lewis Spence, and in Popular Tales of the West Highlands by J. F. Campbell.