Freyfaxi is an American Asatru holiday based on the American Wiccan holiday Lammas. Lammas means loaf mass, that is, a holiday celebrating harvest and the baking of loaves of bread. It is generally celebrated on August 1st. In the early days of American Asatru, Asatruars borrowed Lammas from Wicca and then tried to find an appropriate heathen name for it. They knew that in ancient times, heathens regarded the horse an an appropriate animal for sacrifice. They found the name of a horse in the lore and named the holiday after the horse.
I have been reading The Sagas of the Icelanders and just read the one about the horse. The name of that story is the Saga of Hrafnkel Freysgodhi. The story is a tragedy, in that Hrafnkel brought about his own downfall through his tragic flaw of rashness. Hrafnkel swore a rash oath to kill any man who rode his stallion Freyfaxi, whom he had dedicated to Freyr. Someone rode the horse, and Hrafnkel killed the man. Hrafnkel was outlawed for it. He lost his chieftanship / priesthood, his land, and the horse, too.
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