The Fourth Branch of the Mabinogi belongs to Math fab Mathonwy, lord of Gwynedd and the most powerful magician in medieval Welsh literature. He ruled from Caer Dathyl in the mountains of Eryri, and his court reached west across Anglesey and east as far as the Conwy.
Math had one strange, defining condition: outside of wartime, he could only live if his feet rested in the lap of a virgin foot-holder. It is one of the oddest geasa in Celtic myth, and it sets every event in the Branch in motion. When his nephews Gwydion and Gilfaethwy scheme to remove his current foot-holder, Goewin, so that Gilfaethwy can rape her, they trigger a war with Pryderi of Dyfed as a distraction.
Math's response is one of the most extraordinary punishments in the Mabinogi. He turns his two nephews, in turn, into a stag and a hind, a boar and a sow, a wolf and a she-wolf — each year a different pair, each year forced to mate and bear young, who Math then takes into his own household and raises as men. After three years, he forgives them. The Welsh tradition is rarely so coolly inventive about justice.
It is Math, with Gwydion, who later conjures Blodeuwedd from the flowers of oak, broom and meadowsweet, as a wife for Lleu Llaw Gyffes — a creation that will end in betrayal, murder, and an owl. And it is Math who lifts the curse Arianrhod lays on her own son, weaving a name and arms for him out of magic and patience.
Math is not a hero in the usual sense. He does not fight, he does not quest, he does not love. He sits in his hall with his feet in Goewin's lap, and he listens, and he weighs, and when he acts, the world rearranges itself. He is the closest thing the Welsh tradition has to a king-as-archetype: the still centre around which the magic of the Mabinogi turns.
Wear something inspired by Math fab Mathonwy and you wear the deep, strange heart of medieval Gwynedd — a wizard-king whose stillness was more powerful than any sword, and whose hall, somewhere in the mountains above us, has never quite faded out of the Welsh imagination.