The Mythological Cycle is a conventional grouping within Irish mythology. It consists of tales and poems about the god-like Tuatha Dé Danann, who are based on Ireland's pagan deities, and other mythical races such as the Fomorians and Fir Bolg. It is one of the four main story 'cycles' of early Irish myth and legend, along with the Ulster Cycle, the Fianna Cycle and the Cycles of the Kings. The name "Mythological Cycle" seems to have gained currency with Arbois de Jubainville c. 1881–1883. James MacKillop says the term is now "somewhat awkward", and John T. Koch notes it is "potentially misleading, in that the narratives in question represent only a small part of extant Irish mythology". He prefers T Ó Cathasaigh's name, Cycle of the Gods. Important works in the cycle are the Lebor Gabála Érenn, the Cath Maige Tuired, the Aided Chlainne Lir and Tochmarc Étaíne.
The Tuatha Dé Danann in John Duncan's "Riders of the Sidhe" (1911)
Irish mythology is the body of myths indigenous to the island of Ireland. It was originally passed down orally in the prehistoric era. In the early medieval era, some myths were transcribed by Christian monks, who heavily altered and Christianised the myths. Irish mythology is the best-preserved branch of Celtic mythology.
Riders of the Sidhe, a 1911 painting of the aos sí or Otherworldly people of the mounds, by the artist John Duncan
Cuchulain in Battle by Joseph Christian Leyendecker, 1911
The Fomorians, as depicted by John Duncan (1912)
Folio 53 of the Book of Leinster. Medieval manuscripts are the main source for Irish mythology and early literature.
