Epona

In Gallo-Roman religion, Epona was a protector of horses, ponies, donkeys, and mules. She was particularly a goddess of fertility, as shown by her attributes of a patera, cornucopia, ears of grain and the presence of foals in some sculptures. She and her horses might also have been leaders of the soul in the after-life ride, with parallels in Rhiannon of the Mabinogion. The worship of Epona, "the sole Celtic divinity ultimately worshipped in Rome itself", was widespread in the Roman Empire between the first and third centuries AD; this is unusual for a Celtic deity, most of whom were associated with specific localities.

Although known only from Roman contexts, the name Epona ('Great Mare') is from the Gaulish language; it is derived from the inferred Proto-Celtic *ekwos 'horse', which gives rise to modern Welsh ebol 'foal', together with the augmentative suffix -on frequently, though not exclusively, found in theonyms (for example Sirona, Matrona) and the usual Gaulish feminine singular -a. In an episode preserved in a remark of Pausanias, an archaic Demeter Erinys (Vengeful Demeter) too had also been a Great Mare, who was mounted by Poseidon in the form of a stallion and foaled Arion and the Daughter who was unnamed outside the Arcadian mysteries. Demeter was venerated as a mare in Lycosoura in Arcadia into historical times.

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