The Arrival of the Tuatha De Danann

At the time of the arrival of the Tuatha Dé Danann the race inhabiting Eire was known as the "fir Bolgs" who were divided into three tribes.The "fir Domnann" controlled North Munster, South Munster and Connaught. The "Fir Bolg" controlled Ulster and the "Fir Gaillon" Leincester. At that time their king was called Eochid son of Erc.
It is said that the Tuatha Dé Danann arrived on the 1st of May (Beltaine) bringing with them treasures from their home cities. From Findias they brought Nuada's sword, from Gorias they brought Lugh's lance, from Murias they brought Dagda's cauldron and from Falias they brought the stone of destiny. The gods reached the coast of Ireland in a shrowd of mist to conceal themselves from the Fir Bolgs. Morrigu and her fellow war godesses created fogs, rainstorms and larva to fall on the Fur Bolgs so that they had to take shelter for three days until their own druids overcame the enchantments.
Finally the two sides met and after a period of truce the two sides began a bloody battle where Eochid was slain and the Fir Bolgs defeated. It was in this very battle that Nuada had his hand sliced clean off and, although Diancecht skillfully made him a hand of silver, he was sufficiently disfigured to have to give up the rule of the Tuatha Dé Danann.
And so it was that the Tuatha Dé Danann took control of Ireland. The surviving Fir Bolgs were given Connaught to live in and to this day there are those that claim ancestory to that ancient tribe.