Cú chulainn was the most famous warrior of the Celtic race. He lived in ancient Ulster Ireland before 100 AD. Cú chulainn ’s birth was said to be the result of a Celtic princess swallowing a may-fly that had landed in her cup of wine. She dreamt that the may-fly was the Sun god Lugh and that she would conceive a child by him. She gave birth to a beautiful boy and called him Setanta (Gaelic meaning Knower of Ways usually used as a referrence to the Druids). All the champions, druids, poets, and lawgivers of Ulster vied to teach this mysterious child because they believed him to be the son of Lugh.
When he was seven he defeated all comers at the game of hurley. He was observed by Culann, chief smith in Ulster who invited him to a feast of warriors. Not realizing the boy had not yet arrived Culann unleashed his huge hound to guard his dun (Gaelic = fort) as they celebrated. The hound attacked Setanta who stuffed his hurley ball in the hound’s mouth, grabbed his hind feet, and swung it over his head dashing it’s head into a wall. Culann was angered at the loss of his hound so the boy agreed to guard the dun himself until a new hound was trained. Thus Setanta acquired the name Cú chulainn meaning “Culann’s hound”.
When a Druid prophesied that he who took up arms that day would be the greatest warrior that ever lived, but his life would be short Cú chulainn secured arms at the age of seven. At age 17 he was sent to the Warrior queen Sgathach to learn the art of war. To the Irish the land of Sgathach was a mysterious foreboding place of witchcraft and mystery. The Gaelic word for castle is Dun (pronounced doon). Sgathach’s dun was called Dunscaith on the Isle of Skye which is currently a part of the Clan Donald Lands Trust. To get to Dunscaith Cú chulainn had to journey through a treacherous bog that no man could cross. Could this bog be Rannoch moor that Clan Donald later navigated by night to lose their enemies? At Dunscaith Cú chulainn developed the skill that made him the legendary warrior who could single handedly defeat armies once his war rage or fury came over him. Even back then all of Eire would come against Ulster. Cú chulainn defeated the combined armies of the rest of Ireland. Early monastic documents include the account of St. Patrick raising Cú chulainn from the grave he had occupied for 400 years in order to bear witness of Christianity to Laogaire the Second, High King of Ireland.
Celtic Myths and Legends by Charles Squire from the original ancient Tain Bo Chuailgne from the Book of Dun Cow