This story possibly dates from the twelfth century, but is only available in a fifteenth century version. It is Ireland versus the rest and contains some extraordinary imagery. The themes are all battle related: single combat, cutting off heads, one conquering many, giant champions, magic weapons and boy warriors
The King of the World, Dáire Donn, brought together a great army to take Ireland and put it under tribute. Amongst his leaders were the kings of Greece, France, Norway, the Eastern World, the Saxons and many other exotic personalities.
Fionn was not far away when they landed, but the message took a long time to reach him, and two of his followers held the invaders at bay by challenging them to single combat. The King of the World’s personal champion was thirty feet high and fifteen feet across. Then they summoned the Tuatha Dé Danann under Bodb Dearg to help them and they came and fought against the King of the World’s warriors and held the line. When he finally heard of the invasion, Fionn marched with seven battalions of the Fianna; even so the Irish were outnumbered and Fionn decided on a strategy of daily challenge to be led by a different one of his champions. There were terrible losses on both sides and Fionn was running out of men.
Fearghus of the Sweet Lips went to the high-king in Tara and asked him to help the Fianna, but this was at a time when relations between Fionn and the high-king were rather cool and the latter refused. So Fergus went to the high-king’s son, Goll, and shamed him by saying that he was letting his inheritance slip through his fingers. The high-king’s son, without consulting his father, assembled a force of one thousand and twenty young men and joined Fionn.
The fighting went on for days until one day Fionn asked Fearghus how many men they had left and Fearghus said that they only had one battalion. So he set out again and went to the house of the son of the god, Nuadhu of the Silver Hand who was Fionn’s grandfather. It was said that the King of the World could not be overcome unless his opponent was armed with the sword and shield that was made for the King of the World by the smith of the Fomorians. These were fetched from the King of the Country of the Fair Men by Labran Long Arm, and rushed to Fionn by Aedh son of Aebinn who could move at the speed of a hare or a swallow.
When Fionn uncovered these weapons there rose from them flashes of fire and deadly bubbles. The battle was still raging when finally the King of the World came out to challenge Fionn. When he saw his own weapons in Fionn’s hands he knew that he was doomed; so it was to be and Ireland was saved.