In Manx mythology, the island was ruled by Manannán mac Lir, a Celtic sea god. One of the principal theories about the origin of the name Mann is that it is named after Manannan.
Manannán has strong ties to the Isle of Man, where he is referenced in a traditional ballad as having been the nation's first ruler. On Midsummer, the Manx people offer bundles of reeds, meadow grasses and yellow flowers to Manannán in a ritual ‘paying of the rent’, accompanied with prayers for his aid and protection in and fishing. He is also believed to have been a magician who could make an illusory fleet from sedge or pea shells in order to discourage would-be invaders
According to the Book of Fermoy, a Manuscript of the 14th to the 15th century, 'he was a pagan, a lawgiver among the Tuatha Dé Danann, and a necromancer possessed of power to envelope himself and others in a mist, so that they could not be seen by their enemies.' It was by this method that he was said to protect the Isle of Man from discovery.
In the Manx tradition of folklore, there are many stories of mythical creatures and characters, these include:
The Buggane, a malevolent spirit who according to legend, blew the roof off St Trinian's Church in a fit of rage.
The Fenodyreethe is like a brownie, hob, or sprite in folklore, particular around the Isle of Man. It worked very hard from dusk to dawn at agricultural tasks, such as herding, mowing, reaping and threshing. It's only payment was in food and drink at the farm and it would serve the farmer loyally.
The Glashtyn is a water horse similar to examples in Celtic tradition and folklore, especially in Scotland and Wales. This particular creature often appears as a dark, splendidly handsome young man, with flashing eyes and curly hair. However, he may be distinguished from a real human being by his ears, which are pointed like a horse's.
The Moddey Dhoo, a ghostly black dog who wandered the walls and corridors of Peel Castle.
Mann is also said to be home to fairies, known locally as the little folk or themselves. There is a famous Fairy Bridge and it is said to be bad luck if one fails to wish the fairies good morning or afternoon when passing over it.
An old Irish story tells how Lough Neagh (IN Northern Ireland) was formed when Ireland's legendary giant 'Fionn mac Cumhaill' (Finn McCool) ripped up a portion of the land and tossed it at a Scottish rival. He missed, and the chunk of earth landed in the Irish Sea, thus creating the island (Isle of Man).