Taken in whole or in part from the Ultimate Encyclopedia of Mythology celtic section. I parphrased a lot of the entry so it really isn't a direct quote.
"Cuchulainn, champion warrior of Ulster. His name means 'the Hound of Culann'. He gained this name after killing the ferocious guard dog of the Ulster Smith Culann. His host having lost a faithful guardian, Cuchulainn (at the time called Setanta) offered to take the hound's place. He was forever afterword nicknamed the Hound of Culann. Cuchulainn is known as the Irish Achilles, a larger-than-life fighter whose bouts of temper often caused grief to himself and others. Cuchulainn was unbeatable in combat, until his last campaign, a single-handed defence of Ulster against the army of Queen Medb of Connacht. Even though one arm was withered by a curse and he lost the support of the Goddess Morrigan he slowed the advance of Queen Medb until Ulster could rally it's forces. However their help came too late. Pressed on all sides he was overcome in spite of aid from his divine father, the sun god Lugh. Suffering from a terrible stomach wound Cuchulainn tied himself to a boulder so he could fight to his last breath. The Goddess Morrigan landed on his shoulder in the form of a crow, signaling his death, whereupon his enemies cut off his head and right hand.
His exploits were so widespread that they may have influenced the development of the Arthurian myths in Britian and France."
"Cuchulainn, champion warrior of Ulster. His name means 'the Hound of Culann'. He gained this name after killing the ferocious guard dog of the Ulster Smith Culann. His host having lost a faithful guardian, Cuchulainn (at the time called Setanta) offered to take the hound's place. He was forever afterword nicknamed the Hound of Culann. Cuchulainn is known as the Irish Achilles, a larger-than-life fighter whose bouts of temper often caused grief to himself and others. Cuchulainn was unbeatable in combat, until his last campaign, a single-handed defence of Ulster against the army of Queen Medb of Connacht. Even though one arm was withered by a curse and he lost the support of the Goddess Morrigan he slowed the advance of Queen Medb until Ulster could rally it's forces. However their help came too late. Pressed on all sides he was overcome in spite of aid from his divine father, the sun god Lugh. Suffering from a terrible stomach wound Cuchulainn tied himself to a boulder so he could fight to his last breath. The Goddess Morrigan landed on his shoulder in the form of a crow, signaling his death, whereupon his enemies cut off his head and right hand.
His exploits were so widespread that they may have influenced the development of the Arthurian myths in Britian and France."