Arawn

In Welsh mythology, Arawn was the king of the otherworld realm of Annwn, appearing prominently in the first branch, and alluded to in the fourth. In later tradition, the role of king of Annwn was largely attributed to the Welsh psychopomp, Gwyn ap Nudd. However, Arawn's memory is retained in a traditional saying found in an old Cardigan folktale:

The name Arawn is possibly analogous to the continental theonym Arubianus.

In the First Branch of the Mabinogi, Pwyll mistakenly stumbles into the realm of Annwn and finds white hounds with red ears feeding on a stag. Pwyll chases the hounds off, only to learn that the hounds belonged to Arawn, ruler of Annwn. To pay for the misdeed, Arawn asks 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 has attempted but has been unable to do. Arawn, meanwhile, takes Pwyll's place as lord of Dyfed. Arawn and Pwyll become good friends because when Pwyll wore Arawn's shape, he slept chastely with Arawn's wife.

A friendship between the two realms is retained long after Pwyll's death; in the fourth branch, Pryderi, Pwyll's son and lord of Dyfed has received a gift of otherworldly pigs from Arawn. These pigs are eventually stolen by Venedotian magician and trickster, Gwydion fab Don. Gwydion poses as a bard, and asks to be rewarded for his poems and music with the pigs Pryderi owned. According to Pryderi, he is still in a pact with Arawn and cannot give the pigs to anyone. Gwydion then tricks Pryderi into trading him the pigs (as that is allowed in the deal with Arawn), which eventually leads to Pryderi's invasion of Gwynedd. In the ensuing war, Gwydion kills Pryderi in single combat.

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