The History of Taliesin, in which we encounter the godlike figure, places his birth during the time of King Arthur, at Llyn Tegid (modern Lake Bala) in Gwynedd.
The witch Cerridwen had two children. The one, her daughter, was as beautiful a child as you could ever hope to see; the other, her son Morfran, was so ugly, ill-favored and stupid that he sickened everyone who saw him.
Ceridwen was grieved that Morfran was so horrible, and resolved by her magic arts to make him into such a great bard that no-one would mind his ugliness. She began to cast a great spell. Many were the plants that she cast into her cauldron, many the incantations said over it. An old blind man named Morda was set to keep the fires burning beneath it, assisted by a young boy, Gwion.
The Cauldron of Wisdom and Inspiration must be kept boiling for a year and a day, and then the first three drops from it would impart ultimate knowledge to the one who drank them. But the rest of the liquid would be deadly poison.
Long labored Ceridwen, roaming far to find the rare and exotic herbs she required, and so it chanced that she fell asleep on the last day of the spell. The boy Gwion was stirring the brew when three drops flew out onto his thumb, and they were scalding hot, so that he thrust it into his mouth to stop the burning. Instantly, he had the wisdom and inspiration of ages, and the first thing that occurred to him was that Ceridwen would be very angry. These were the three drops of awen, which resulted in Gwion's enlightenment.
He ran away from the house of Ceridwen, but all too soon he heard the fury of her pursuit. Using his new magical powers, he turned himself into a hare. She turned into a greyhound bitch, and gained ever more on him. He came to a river, and quick as thinking became a fish. She became an otter. He leapt from the water, and in the middle of his leap became a bird of the air. The witch Ceridwen became a hawk. In desperation, he looked down and saw a pile of wheat. He dived, landed, and as it scattered he turned into a single grain. Then she landed and became a hen, and pecked at the grain until she had swallowed Gwion.
Soon after, Ceridwen found herself with child, though she had lain with no man. When she realized that the baby was Gwion, she resolved to kill it, and Morfran wanted her to also, in revenge for his not becoming a bard. In due course, the babe was born, and Morfran would have slaughtered him on the spot, but the mother said no, because it was the most beautiful child ever seen. But she took him and, sewing him in a bag, set him adrift on the ocean.
He is then found by Elphin, son of Gwyddno Garanhir, who raises the boy and names him "Taliesin" for the radient brow the infant possesses. The infant is preternaturally gifted, able to speak at birth.
The king of the land at that time was Maelgwn, a somewhat vain man who surrounded himself with toadies and fawning sycophants. The year that Taliesin turned thirteen, Elphin received a summons from the king, demanding his presence at the Christ Mass feast at midwinter.
As they all sat around the high table, the other men vied with one another to see who could praise Maelgwn the most. Elphin was an honest man, and he couldn't honestly say that the king's bards were better or the queen a fairer woman, than those waiting at his home.
"What, so silent, Elphin? Can our loyal subject then find nothing to praise his king for?" said Maelgwn.
"Well, my lord," said Elphin, "I would say that though I am not a king, yet my wife is as fair and as virtuous as any woman in the kingdom - and my bard the best in Gwynedd."
"Insolence!" roared Maelgwn. "Throw him in our deepest dungeon! Let him be chained there until the falsity of his monstrous claim can be shown once and for all! And we think we know just how to do that..."
Taliesin was out skating. As he bent down to take the skates off, he glanced at a patch of ice, and fell into a trance, where he saw all that had befallen Elphin. When he woke, he rushed home to tell Elphin's wife.
Maelgwn had a son named Rhun, a lecher so revolting that to be seen with him would tarnish a woman's reputation beyond repair. This son he sent to Elphin's home, to seduce his wife and show the falsity of his claims. When Rhun came to the gate, he was welcomed, if not warmly, then civilly, by young Taliesin. He showed the prince into the hall, where sat a woman dressed in finery, with rings upon her fingers and a golden torque. She made him welcome and they supped together. Rhun poured cup after cup of wine for her, and foolishly she drank it all. Soon she was giggly and silly, and she assented to his request to withdraw with him to some place more private. Rhun waited until she fell asleep in a drunken stupor, then tried to remove the ring from her plump hand. It would not come off, so quick as lightning he cut the finger off, ring and all.
When Maelgwn told Elphin what had transpired, Elphin did not believe it and asked for proof. The king produced the severed finger bearing the ring. Elphin looked closely and declared it not the finger of his wife and that Rhun had been tricked.
Maelgwn was furious and challenged a competition between their bards. Elphin was taken back to his cell.
Taliesin was already seeing about provisions for the journey, while Elphin's wife looked after the poor nine-fingered maidservant. He arrived at the court two days later, and slipped through the gates. He made his way to the throne room and sat in the corner. When the king's bards filed in, he pouted his lips at them and played blerwm, blerwm on them, and the bards stood still and played blerwm, blerwm on their lips instead of praising Maelgwn. Maelgwn finally ordered a guard to strike Heinnin Fardd, his chief bard. This broke their trance enough that Heinnin Fardd could explain to Maelgwn that there was a devil in the form of a child who had cast a spell on them.
Then Maelgwn had Taliesin brought out, and questioned him.
"I have come to salvage Elphin's honor and his freedom. Taliesin am I, primary chief bard to Elphin.
"Primary chief poet
Am I to Elphin.
And my native country
Is the place of the Summer Stars.
"John the Divine
Called me Merlin,
But all future kings
Shall call me Taliesin.
Maelgwn scoffed and questioned that a mere child would be able to beat his bards who had trained for twenty years.
The contest was announced and Taliesin suggested it should be to compose a poem on the wind with the King to be the judge. Maelgwn was getting bored now, and declared that the poem had to be written in twenty minutes.
Heinnin Fardd and the king's bards huddled in the corner, consulting scrolls of rhymes and metaphors. Every so often, one let out a yelp of frustration. Taliesin lounged on the floor.
When the time was up, the king's bards stood in a line before the throne and bowed.
"O greatest of kings, hear our song.
Blerwm, blerwm,
blerwm, blerwm,
blerwm, blerwm,
blerwm, blerwm."
"Knaves! Fools! Miserable swine! Was it for this that I paid you in gold and precious gems?" The court had never seen Maelgwn so angry. The bards groveled in the rushes. "Mighty king, it was not our fault! It's that demon child."
Taliesin, admittedly, was smirking in a most irritating fashion.
"So it's my turn?" he asked. He stood up straight and began. While he sang, a great wind arose and buffeted the castle, shaking it to its foundations. Maelgwn was afraid, and he called for Elphin to be brought out.
As soon as Elphin was brought out, Taliesin stopped the wind, and sang a new song that caused Elphin's chains to fall away from his ankles and wrists. Then he cried out to Elphin's wife to enter the hall, and she held her hands up so that everyone could see that she had ten fingers. Maelgwn was angrier than ever.
He then challenged Elphin, with a race between their horses. Taliesin told Elphin to accept.
