Tuatha De Danann
In Irish-Celtic mythology, the Tuatha De Danann ("People of the goddess Danu") are the Irish race of gods, founded by the goddess Danu. These gods, who originally lived on 'the islands in the west', had perfected the use of magic. They traveled on a big cloud to the land that later would be called Ireland and settled there.
Shortly after their arrival they defeated the Firbolg at the first battle of Mag Tuireadh. In the second battle of Mag Tuireadh they fought and conquered the Fomorians, a race of giants who were the primordial inhabitants of Ireland. The Tuatha De dealt more subtly with the Fomorians than with the Firbolg, and gave them the province of Connacht. There was also some marrying between the two races.
The Tuatha De themselves were later driven to the underworld by the Milesians, the people of the fabulous spanish king Milesius. There they still live as invisible beings and are known as the Aes sidhe. In a just battle, they will fight beside mortals. When they fight, they go armed with lances of blue flame and shields of pure white.
Important members are of the Tuatha De are: Dagda, Brigid, Nuada, Lugh, Dian Cecht, Ogma, and Lir. The goddess Danu can also be identified with the Welsh goddess Don.