One with the Spirit :Perhaps one of the best known of the Celtic deities associated with horses is the goddess Epona. She is seen as a protector of horses, donkeys and mules. She is the only Celtic god that was also worshipped in Rome. Little is written about Epona other than references in some Roman literature and on inscriptions on carved images of the goddess. The name Epona derives from Gaulish which was a Celtic language spoken in Gaul and other parts of continental Europe from around the 6th century BC to the 6th century AD. She is usually depicted riding or standing between two horses.