Celtic World of Morgan Llywelyn9 books in series
The Horse Goddess Publisher's Summary
Troy is in crumbling ruin and Athens is rising far to the south. It is a time when mortal men and women are becoming gods and goddesses as news of their extraordinary adventures sweeps across the land. In this world, Epona, a woman whose life is celebrated in legend, meets Kazhak, a Scythian warrior and prince.
Their stormy love affair sends them sweeping across eighth-century Europe, pursued from the Alps to the Ukraine by Kernunnos - a mysterious Druid priest known as the "Shapechanger."