The jealousy of Catholic against Protestant, of south against north, were too deeply rooted.
Byron's description, "[The] immemorial wood Rooted where once the Adrian wave flowed o'er," is probably true; but there is no evidence that it was in historic time that this change took place.
But it is not so well understood that slavery discharged important offices in the later social evolution - first, by enabling military action to prevail with the degree of intensity and continuity requisite for the system of incorporation by conquest which was its final destination; and, secondly, by forcing the captives, who with their descendants came to form the majority of the population in the conquering community, to an industrial life, in spite of the antipathy to regular and sustained labour which is deeply rooted in human nature.
But we are not to suppose that even he, latitudinarian and innovator as he was, could have conceived the possibility of abolishing an institution so deeply rooted in the social conditions, as well as in the ideas, of his time.
His doctrine was rooted in the old Iranian - or Aryan - folk-religion, of which we can only form an approximate representation by comparison with the religion of the Veda.