Branwyn

Branwen, Daughter of Llŷr is a major character in the Second Branch of the Mabinogi, which is sometimes called the "Mabinogi of Branwen" after her.

Branwen is a daughter of Llŷr and Penarddun. She is married to the King of Ireland, but the marriage does not bring peace.

The story opens with Branwen's brother, Brân the Blessed, giant and King of Britain, sitting on a rock by the sea at Harlech and seeing the vessels of Matholwch, king of Ireland, approaching. Matholwch has come to ask for the hand of Branwen in marriage. Brân agrees to this, and a feast is held to celebrate the betrothal. While the feast is going on, Efnysien, a half-brother of Branwen and Brân, arrives and asks why there are celebrations. On being told, he is furious that his half sister has been given in marriage without his consent, and vents his spleen by mutilating Matholwch's horses. Matholwch is deeply offended, but conciliated by Brân, who gives him a magical cauldron which can bring the dead to life; he does not know that when the dead are brought back, they will be mute.

When Matholwch returns to Ireland with his new bride, he consults with his nobles about the occurrences in the Isle of the Mighty. They are outraged and believe that Matholwch was not compensated enough for the mutilation of his horses. In order to redeem his honor, Matholwch banishes Branwen to work in the kitchens.

Branwen is treated cruelly by her husband Matholwch as punishment for Efnysien's mutilation of the horses, though not before she gives birth to an heir, Gwern. She tames a starling and sends it across the Irish Sea with a message to her brother and Brân brings a force from Wales to Ireland to rescue her.

Some swineherds see the giant Brân wading the sea and report this to Matholwch, who retreats beyond a river and destroys the bridges. However, Brân lays himself down over the river to serve as a bridge for his men, he said ("He would be a leader, let him be a bridge").

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