Menw son of Teirgwaedd is one of Arthur’s men in Culhwch and Olwen where he appears as a wizard and shape shifter. Menw also appears in Triad 27 as one of the three enchanters of Britain along with Track (Coll) son of Tracker (Collifrey) and Drych son of Cibddar. Triad 28 tells of the three enchantments of Britain, the enchantment of Math son of Mathonwy which he taught to Gwydion son of Dôn, the enchantment of Uthyr Pendragon which he taught to Menw son of Teirgwaed, and the Enchantment of Gwythelyn the Dwarf which he taught to his nephew Track son of Tracker. Menw appears, along with Trystan son of Tallwch and Eddilig the Dwarf as one of the Three Enchanter Knights in the 15th century list of Twenty-four Knights of Arthur’s court.
Menw in Culhwch and Olwen[]
Menw son of Teirgwaedd is listed in the long list of Arthur’s men. Annynawg son of Menw son of Teirgwaedd is also listed.
Menw is chosen by Arthur as one of the men to set out with Culhwch to seek for Ysbaddaden Chief Giant and his daughter Olwen. As translated by Davies (2007, p. 190):
Arthur calls on Menw son of Teirgwaedd, for should they come to a pagan land he could cast a spell on them so that no one could see them, but they could see everyone.
When the group see a giant shepherd with a dog bigger than a nine-year-old stallion and wish to talk to the shepherd, Menuw says that he will cast a spell on the dog so that the dog will not harm anyone.
Later the story tells (Davies, 2007, p. 208):
And after killing Ysgithrwyn Pen Baedd, and his retinue went to Kelli Wig and Cornwall. And from there he sent Menw son of Teirgwaedd to see whether the treasures were between the ears of Twrch Trwyth, because it would be pointless to go to fight with him unless he had the treasures. It was certain, however, that he was there. He had destroyed one-third of Ireland. Menw went to look for them. He saw them at Esgair Oerfel in Ireland. And Menw turned himself into a bird, and settled above his lair, and tried to snatch one of the treasures from him. But indeed he got nothing save one of his bristles. The boar got up in full fury, and shook himself so that some of the poison caught him. And from then on Menw was never without affliction.
For the final slaughter of Twrch Trwyth (Davies, 2007, p. 212):
And Mabon son of Modron went with him [Twrch Trwyth] on Gwyn Myngddwn, Gweddw’s steed, into the Hafren [Severn], and Goreu son of Custennin and Menw son of Teirgwaedd, between Llin Lliwan and Aber Gwy [Wyemouth].
Magic of Uther Pendragon[]
In the story of Uther Pendragon as told by Geoffrey of Monmouth and later writers, Merlin is able to change his own shape, and Uther’s and Ulfin’s by his magic arts. This triad suggests that in the tale here told Uther Pendragon used his own magic, magic which Uther Pendragon later taught to Menw or by other means passed on to Menw.
The Enchanter Knight in Jaufré[]
The Provençal romance of Jaufré begins at Arthur’s court at Carlisle, at Pentecost, when no adventure or strange tiding comes to court. Finally, tired of waiting, Arthur decides that he and his Knights of the Round Table will ride out in search of adventure if needs be. They ride towards Broceliande, when a faint cry is head in the distance. Arthur orders his knights to remain behind while Arthur rides alone to find the source of the cry.
Arthur comes across an old woman making great sorrow in the doorway to an ancient mill. She complains to Arthur that a beast is therein and that it is eating all her grain. Arthur indeed sees within the mill a great horned beast eating the grain. Arthur enters the mill and attacks with his sword Caliburn to no effect; the beast ignores the blow as though it did not perceive it. Then Arthur seizes the beast by its horns, intending to strike a blow with his fists, but finds that his hands are now stuck immovably to the horns of the bull by some enchantment.
The beast now raises its head and issues from the mill, bearing the helpless king before it. Gawain has followed and sees this and summons the other knights. But Arthur forbids them to take any action to free him lest they too become stuck. The beast, with the King fastened to its horns, now climbs a tall rock overhanging a valley, and stretches out its head so that the king is hanging from its horns over a precipitous drop. The barons, fearing that the king may fall, doff their garments and place them in a pile at the place where the king would land if he fell.
Suddenly the best itself leaps forward and down onto the pile of garments, with the king still clinging to its horns. When the beast touches the ground, it transforms into a knight and the king is standing there free.
The knight transformed from the beast is recognized by all as on of the Round Table and also a master of the seven arts, well versed in magic, and well loved by all. The knight had formerly made a wager with Arthur that if he might get the power to change his shape before them all, and to prove it, then Arthur should grant to him a golden cup, a fleet charger, and the kiss from whatever maid he wishes.
Arthur proclaims that the knight has won the wager and declares a feast to honor him.
It cannot be known whether some tale of Menw might lie behind this story.