Brego in the books was not a horse. Not Aragorn’s horse. Not Theódred’s horse. He would probably be quite insulted to be called a horse, in fact.
Brego was the second of the Kings of Rohan, son of Eorl the Young, and father of Baldor, Aldor and Eofor – the ancestor of Éomund and Éomer.
It was he who completed the golden hall of Meduseld. At the feast in Meduseld to celebrate its completion, his son Baldor vowed to tread the Paths of the Dead and did not return. Brego died of grief the next year.
by atalante_star
