Andrea Dworkin, Woman Hating (Dutton) 1974, pgs 119-121:
"The Christian notion of the nature of the Devil underwent as many transformations as the snake has skins. In this evolution, natural selection played a determining role as the Church bred into its conception those deities best suited to its particular brand of dualistic theology. It is a cultural constant that the gods of one religion become the devils of the next, and the Church, intolerant of deviation in this as in all other areas, vilified the gods of those pagan religions which threatened Catholic supremacy in Europe until at least the 15th century...The Church had a slew of dieties to dispatch and would have done so speedily had not the old gods their faithful adherents who clung to the old practices, who had local power, who had to be pacified. Accordingly, the Church did a kind of roulette and sent some gods to heaven (canonizing them) and others to hell (damning them).
...[Unlike the Greco-Roman gods,] in northern Europe the old gods did not fare as well. The peoples of northern Europe were temperamentally and culturally quite different from the Latin Christians, and their religions centered around animal totemism and fertility rites. The 'heathens' adhered to a primitive animism. They worshiped nature (archenemy of the Church)...
These pagan rites and dieties maintained their divinity in the mass psyche despite all of the Church's attempts to blacklist them. Some kings of England were converted by the missionaries, only to revert to the old faith when the missionaries left. Others maintained two altars, one devoted to Christ, one to the horned god."

See also Adler and Povey and Baba Yaga Emporium.....