Arawn

In Welsh mythology, Arawn was the Lord of the Underworld, which was called Annwn.

Some of the more prominent myths about Arawn include the incident in which Amaethon stole a dog, lapwing and a white roebuck from Arawn, leading to the Cath Godeau, which Arawn lost to Amaethon and his brother, Gwydion.

In the Mabinogion, Pwyll mistakenly set his hounds upon a stag, only to discover that Arawn had been hunting the same animal. To pay for the misdeed, Arawn asked Pwyll to trade places with him for a year and a day, and defeat Hafgan, Arawn's rival, at the end of this time, something Arawn had attempted to do, but had been unable to. Arawn, meanwhile, took Pwyll's place as lord of Dyfed. Arawn and Pwyll became good friends because, though Pwyll wears Arawn's shape, he sleept chastely with Arawn's wife.

In Welsh folklore, Arawn rides with his white, red-eared hounds (the Cwn Annwn or Hounds of Annwn) through the skies in autumn, winter, and early spring. The baying of the hounds is identified with the crying of wild geese as they migrate, and the quarry of the hounds are the souls of the damned, being chased back to Annwn (sometimes to the abode of the Brenin Llwyd or Grey King).

Arawn is also a prominent character in The Chronicles of Prydain, a series of fantasy novels written by Lloyd Alexander that revolve around Welsh myths.