About the Danann
The Tuatha de Danann (people of Danu) were the fifth group of people to settle in Ireland. They were ruled by Nuada, who, in some accounts, was a son of Danu, the patron goddess of the Danann. The chief Druid of the Danann was The Dagda, another son of Danu (in some accounts). The Danann probably originally came from Scandinavia. Like their predecessors, the Fir Bolg they were descendants of Nemed.
The Danann invade Ireland
Nuada, king of the Danann, led his people to Ireland after leaving Scandinavia for unknown reasons. They arrived on May 1st, and burned their ships so they could not leave. After arriving, Nuada sent scouts to speak with the king of the Fir Bolg, Eochaid mac Eirc. When Eochaid refused to share the island with the Danann, Nuada gathered an army and fought the Fir Bolg on the plain of Mag Turied. During the battle, Sreng, the Fir Bolg champion, cut off one of Nuada's hands. However the Fir Bolg also had a disadvantage. During the battle, King Eochaid became overcome with thirst and ran off in search of water. The Morrigan found him, and seeing that he had lost his sword, killed him.
The tyranny of Bres
Though the Fir Bolg had been defeated, Nuada could no longer rule because of his missing hand. So the Danann chose Bres to be their new king. Though he was one of the Danann, Bres was half Fomorian, and he favored his Fomorian kin over his Danann kin. Bres began oppressing the Danann, forcing them to work hard for their food. To make matters worse, Bres made the Danann give a third of their crop and a third of their children to the Fomorians. Eventually, the Danann became so fed up with Bres' tyranny that they became desprate to have Nuada restored, despite his mutilated hand. So Goibniu, the Danann smith, forged a hand out of silver, and Dian Cecht, the Danann physician attached it to Nuada's hand using a combination of surgery and magic. Thus, Nuada was restored to the throne, and he gained the epithet "Nuada Airgetlam" (Nuada of the silver hand).
Nearly twenty years after Nuada was restored to the throne, a young man named Lugh came to his castle, and warned that Bres had gone to Balor (who happened to be Lugh's maternal grandfather), in an attempt to regain the throne. Discovering that the Fomorians wer plotting against his people, Nuada allowed Lugh to become his general.
The defeat of the Fomorians
After seven years of preparation, both the Danann and the Fomorians were both ready for war. The two armies met for battle on the plain of Mag Turied, where the Danann had fought the Fir Bolg. During the battle, Balor killed killed Nuada with his poisonous eye, but Lugh killed Balor with a sling, thus fufilling an old prophecy that Balor would be killed by his grandson.
Danann kings after Nuada
With the death of Balor, the Fomorians fled from Ireland and were never heard from again. However, with the death of Nuada of the silver hand, the Danann needed a knew king. They eventually elected Lugh, despite the fact that he was half Fomorian, like Bres. Lugh ruled for forty years, and when he was killed (see Lugh's page), The Dagda succeeded him. When The Dagda died, Dalbaeth, one of his grandsons, succeeded him. Dalbaeth ruled for ten years, and then his son Fiacha succeeded him. Fiacha, like his father, ruled for a decade. When he died, Mac Cuill, Mac Cecht, and Mac Griene succeeded him, the three of them ruling together. They were the last Danann kings before the coming of the Milesians.
The arrival of the Milesians
Mac Cuill, Mac Cecht, and Mac Griene ruled Ireland for 27 years before Ith arrived (see Ith). The three Danann kings murdered Ith, due to a misunderstanding. Ith's kinsmen, the Milesians, invaded Ireland and avenged his death, killing many of the Danann. When the Danann discovered that they were no match for the Milesians, the spirit of The Dagda appeared and led the surviving Danann to Tir na nOg, where they became immortal.