Epona the All Mother

That foal's storybook is probably a glimpse into pony culture thousands of years ago, before there was an Equestria and maybe before alicorn ponies. The story elements of relevance that I'd place emphasis on are: winter, snow, Epona, strange alicorn, crystal hare, land before ponies, north, a time without seasons, weather as an instrument of harmony and a benign/tamed windigo. Also: the story predates Crystal Empire princesses and was probably adapted to include Equestria to make it relevant when this book was printed about a thousand years ago. Epona is a very old legend. I wonder who she retrieved from the south to combat the windigo in earlier versions and what did the crystal ponies call Equestria back then?