Gronw

Gronw Pebr, also named Gronw ap Pebr, is a figure in medieval Welsh legend best known from the tale material that underpins the Mabinogion. He is described as a nobleman and the lord of Penllyn, who becomes involved in a treacherous plot against Lleu Llaw Gyffes, the magical son of Arianrhod.

In the narrative, Gronw collaborates with Blodeuwedd, a woman created from flowers to be Lleu’s wife, to murder Lleu. The plot centers on the use of a weapon capable of killing Lleu under the right circumstances, a scheme embedded in the tale’s magical and prophetic elements. The murder is carried out, but the story continues with themes of retribution and justice. In most versions, Gronw’s treachery leads to his downfall, and Blodeuwedd is punished for her role in the conspiracy by being transformed into an owl.

Scholars read Gronw Pebr as a symbolic figure representing betrayal and the consequences of treachery within Welsh myth. The tale exists in several manuscript variants, reflecting broader patterns in the mythic cycles associated with the Mabinogion, including motifs of magical protection, metamorphosis, and moral consequence.

Etymology: The name Gronw is treated as a Welsh personal name, with Pebr (often rendered as ap Pebr) indicating his patrilineal descent. While a relatively minor character in surviving texts, Gronw’s actions illuminate central themes in the Welsh mythic repertoire.