Lugh was one of the greatest heroes of the Tuatha De Danaan.  Also known as Lugh of the Longarm, he is today celebrated during the festivals at Alban Heruin and Lughnasadh.  Lugh cared for the spear of Gorias and was known for his skill in weapons and crafts.  The Welsh know him as Llew, son of Arianrhod, the ruler of Caer Sidhi and Guardian of the Silver Wheel.  Lugh has inspired Celtic heroes  such as Arthur, Lancelot and Cu Chulainn.

Cu Chulainn:

Cu Chulainn's given name was Setanta, but he changed his name after accidentally killing the watch dog of the smith Culann.  He took the place of the dog and vowed to guard the pass into Ulster and became known as a hound of Culann.  Lugh is mentioned often as his father but it appears that may be only within the spiritual realm. 

Cormac:

Cormac Mac Airt is probably the most famous of the ancient kings of Ireland, now thought to be an authentic historical king. Cormac was the son of Art son of Conn of the Hundred Battles. He ruled Tara, the seat of the High Kings of Ireland, for forty years (probably 227 - 266 CE) and under his rule Tara flourished. He was famous for his wise, true, and generous judgments. Cormac owned the wonderful gold cup given to him by the sea-god Manannan Mac Lir in the Land of the Living. If three lies were spoken over it, it would break in three; three truths made it whole again. Cormac used this cup during his kingship to distinguish falsehood from truth. When Cormac died, the cup vanished, just as Manannan had predicted it would.

Finn Mac Cumhail:

Finn and the Fianna continued to fight in great battles and were acknowledged figures in Celtic history. It was said that in the fields of daring, courageousness, and skill the Fianna were unequaled and that no man could hope to be better in magic, poetry, or wisdom then Finn Mac Cumhail