Emerald Isle

The Tale of Fergus Mac Leide

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Irish and Celtic myths and legends, Irish folklore and Irish fairy tales from the Historical Cycle

A Swift Hand Brings a Bad End

In the time of High King Lugaid Luaigne, that is around the age when Fionn Mac Cumhaill and his Fianna fought in defence of the great land of Ireland, a dispute arose in the northern Kingdom among the men of the Ulaid, for instead of there being only one king of Ulster, there were two!

Well, as anyone who knows anything about kings will tell you, this state of affairs couldn't last very long, and indeed it didn't. The king of the upper half was called Fergus, and the king of the lower half was Conghail, and so often did they dispute and feud that the people of the kingdom asked the High King to intervene and pick one.

The High King Lugaid considered the merits of each, and in the end decided Fergus was the best man to be the king, for he paid his taxes handsomely and when they were due. To seal the deal he granted Fergus his daughter Findabair in marriage, as was the custom at the time, and remained the custom for long after, but Conghail was less than satisfied with being ousted, so he decided to claim his right by the red edge of a spear!

His rebellion against Fergus failed, so he turned aside from that goal and marched instead on Tara, where he surprised and killed the old High King, cutting his head clean off his shoulders and taking the crown before the remains hit the ground. Wasting no time, he kicked Fergus off the throne of the north and put his own brother Ross in charge instead.

However, neither Ross Rua nor High King Conghail lasted very long after that, and when both fell in the battle of Lough Foyle, Fergus was once again made lord and master of the Kingdom of Ulster and the men of Ulaid.

Seven cumals of gold and silver as well as seven cumals of land and seven cumals of bondswomen were given to him for the offences he had suffered, and he exiled his enemies to be set adrift far out at sea, with the distance to be decided by the amount of trouble they had caused him.

Peace at last came to the northlands, and Fergus rode with his charioteer Muena to the shore after the sentence was carried out. There he fell asleep, for his efforts had been as great as those of seven strong men, but as he slept, who should appear but three sea-sprites intent on taking him beneath the waves with them!

They dragged him slowly and carefully, still sleeping, across the sandy beach, and almost succeeded in their goal only for when his feet touched the cold water he came fully awake, and seized the three – one in each arm and the third crushed against his powerful chest!

“Life for life!” cried the head of the sea-fairies, and Fergus was exultant, for he knew that having these creatures in his power, he was entitled to anything he wished, so long as they could provide it. The chief grabbed hold of Fergus' chest and cheek as he submitted, which mystified the king, and he asked “why do you do that?”

“That,” said the strange sprite, “is one of the rules of fair combat with us.” And after that men throughout Ireland would hold the chest and cheek when they surrendered or appealed to another's honour.

Indicating that he would accept their surrender, he asked them for a charm to allow him to pass underwater, beneath the waves of pools, lakes, rivers and the ocean itself.

“It shall be done!” intoned the sprite, “except for one thing only – never shall you go beneath the waves of Lough Rudraige which is in your own kingdom.” Then they gave him herbs to put in his ears, or some tales tell it was a fish cloak of scales he was to wrap about his head, letting him swim like a fish where he would.

Being a king and strong of will as any king, one day Fergus decided he'd go ahead and dive beneath the waves of Lough Rudraige anyway! So he left his chariot and charioteer on the shore and dove deep. But the lake was not empty and from its depths there arose a terrifying monster whose name was Muirdris. This vast serpent inflated and contracted itself like a smith's bellows, and when Fergus saw it his mouth was pulled back past his ears.

He got out of the lake in a hurry, and went to his charioteer.

“How do I look?” he asked, for he could feel there was something amiss with his features.

“Not great,” admitted the charioteer, “but a few nights sleep will see you right.”

So Fergus lay down to recuperate from his shock, and the charioteer went to the assembly of the men of Ulster who sat in the strong place at Emain Macha. He told them the whole sorry tale, and they held council to decide what to do, since nobody who was blemished in body was allowed to be king.

All agreed that Fergus should be allowed to remain king, for he had the respect of the people and the wise men, so they cleared out all the fools and halfwits from the court in case any of them should pass comment and let the king know his flaw. All mirrors and reflective surfaces were removed, and they made a rule that Fergus should always have his head washed while lying on his back so that he might not see his own reflection in the water.

And so for seven years the king was guarded in this manner, until one morning he asked one of his bondsmaids to wash his head, but thinking she was a little slow about it, he gave her a lash with his whip to speed her along. Her anger and resentment spilled over and she started laughing at his distorted features, mocking him roundly.

With that he drew out his bitter sword Caladbolg whose sharpness was such that it could cut  sunlight into rainbows, and he clove her in two halves on the spot! Covered now in shame and grief he fled Emain Macha and returned to the fateful Lough Rudraige where the monster awaited him still, and without further ado he plunged beneath the waves.

For a whole day and a night the waves of the lough seethed and boiled with the fury of the struggle taking place, and its waves lapped the tops of the surrounding hills. As the sun rose the next day however, he crawled out of the lake with the monster's head in his hand.

“I am the survivor!” he declared to the onlookers, and sank down dead on the spot, and for a whole month the lough remained red from the battle between them.

And so of this was sung:

King Fergus, son of Léide
Went on the sandbank of Rudraige;
A horror which appeared to him — fierce was the conflict —
Was the cause of his disfigurement.

Lough Rudraige can be found on the map below.


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