On the Fact that (According to Sean O'Callaghan's Book, "To Hell or Barbados") in Great Britain, Numerous Pamphlets Were Published All Throughout the Early 17th Century Which Routinely Depicted the Irish as a Vile, Subhuman Species, Undeserving of Pity and Mercy

Not that the Puritans of England needed much prompting to hate the Irish, mind you, but when you also get a dose of verbiage such as, "....the very offal of men, dregs of mankind, reproach of Christendom the bots that crawl of the beast's tail....", etc., it's easy to see how that virulent hatred could morph into something far worse; i.e., ethnic cleansing.