Bulfinch's Mythology: The Age of Chivalry by Thomas.
Branwen, Daughter of Llyr In the second branch, Branwen, sister of Bendigeidfran (aka Bran the Blessed), king of Britain, is given in marriage to Matholwch, king of Ireland. Branwen's half-brother Efnisien insults Matholwch by mutilating his horses, but Bendigeidfran gives him new horses and treasure, including a magical cauldron which can restore the dead to life, in compensation.
The Mabinogion. From 'Branwen the Daughter of Llyr'. Warner, et al., comp. 1917. The Library of the World's Best Literature.
Bendigeid Vran (behn-DIH-geed vran), the son of Llyr and king of the Island of the Mighty. While making war on the Irish because of their treatment of Matholwch and Branwen, he is killed by a.
Branwen, Daughter of Llyr: A Study of the Irish affinities and of the Composition of the second branch of the Mabinogi. Cardiff, University of Wales Press, 1958. Some interesting parallels between the Welsh second branch, and various Irish texts. Rees, Brinley and Alwyn Rees. Celtic Heritage: Ancient Tradition in Ireland and Wales.
Gigantic Bran the Blessed, the eldest of Llyr’s sons by Pandarin, seeks to unite the Old and New tribes by a peace-marriage between his sister Branwen and Matholuch, king of Ireland.
Branwen (“white raven”) a daughter of Llyr and Penarddun, and sister of Bran, and Manawydan, and half-sister of Nisien and Efnisien. Matholwch of Ireland sued for her hand, and gave horses to Bran. Efnisien mutilated the horses, nearly precipitating warfare, but Matholwch was appeased by the gift of a cauldron that could resurrect the dead.
The eleven medieval Welsh tales are collectively referred to as the Mabinogion. The word mabinogion is based on a manuscript error; technically only the first four tales are the Mabinogi. I prefer to use the word Mabinogi to refer to the four branches, and Mabinogion to refer to the complete collection of eleven tales.