Fomorians were a group of semi-divine races such as Goblins and Giants and other races who inhabited Ireland in pre-historic times to the ancient times when they were conquered by the Danu group of Nemedians. The Formorians were constantly warring against invading groups. They were beings who preceded the gods. The gods that defeated them and proceeded them were the Tuatha Dé Danann . The Danann were similar to the Greek Titans. They bore many similarities such as they both wanted to teach humans forbidden advance technology. The Danann showed up around the time of the sea peoples migration in the eastern Mediterranean. about 1500 years after the great flood in the year 1477 BC.
It has been suggested that the fomorians represent the gods of chaos and wild nature, as opposed to the Tuatha Dé Danann and Fir Bolg, who represent the gods of human civilization and virtue. Alternatively, they may represent the gods of a proposed pre-Goidelic population of Ireland.
They are sometimes said to have had the body of a man and the head of a goat, according to an 11th century text in Lebor na hUidre (the Book of the Dun Cow), or to have had one eye, one arm and one leg, but some, for example Elatha, the father of Bres, were very beautiful. Bres himself, for example, carries the epithet "the Beautiful."