The greatest rivers have many source just as the Celtic Folk Religions which are some of the richest and most complex sets of beliefs in the world do not have a single source. The Celtic belief system comes from many lands and many peoples who exchanged ideas, philosophies and most importantly fairies and deities. Such exchanges in religious knowledge was common, thus Arito the Celtic Bear Goddess is likely of Ugric origin and Celtic Shamanism was likely greatly influenced by the Ugrics and Altaic peoples.
Such influences and origins provide those who are studying folk religions with advantages in better understanding a given people because while many aspects of the Celtic Folk Religions have been lost to Christian Raiders and the steady decay of time, some of the missing pieces to the puzzle that is the Celtic Folk Beliefs can still be found among those who once shared a religion with or influenced the Celtic peoples. Further the study of these related folk religions can aid those who are trying to build relationships with Celtic Fairies will gain insights into additional ways to do so.