Branwen ferch Llŷr

Branwen ferch Llŷr is one of the Four Branches of the Mabinogi, a collection of Welsh tales compiled between the late 11th and early 13th centuries. This specific branch tells the story of Branwen, the sister of Brân the Blessed, the king of Britain. She marries Matholwch, the king of Ireland.12

However, Branwen's half-brother, Efnisien, causes conflict through treacherous acts, leading to a devastating war between Ireland and Britain. The war results in few survivors, including Branwen, a wounded Brân, and seven other men who return to Wales. Llyr, Branwen's father, is a figure in Celtic mythology associated with the sea, and his children, including Brân and Branwen, were considered powers of darkness in conflict with the powers of light.12