Debates over national dividing lines can get heated. Consider the 17th century discussions over the two philosophers John Duns Scotus and John Scottus Eriugena.
In 1620, a book by the bishop of Ossory David Rothe, Brigida thaumaturga, was published in Paris. It was on the surface an account of the life of St Brigid of Kildare, but that life is used as a metaphor by Rothe for the medieval mission of the Irish to Europe and of the mission of clergy to Ireland (a Catholic country under Protestant rule). The latter required financial security for Irish seminary students, which was their due (according to Rothe) given the huge contribution the Irish had made to France in the past, scholastically and religiously, including the work of John Scottus Eriugena.
Not the type of thing that would have the writer called a “devil”, one might think, but that was not all Rothe wrote. The work also targets Scottish scholar Thomas Dempster who claimed a large number of Irish saints and scholars for Scotland. As the historian Liam Chambers points out, this claim undermined Rothe’s argument for French aid for the Irish and left the Irish Counter-Reformation without native saints. Roth systematically rebutts Dempster’s claims, even going so far as to say all described as “Scotia” or Scots in the Middle Ages are Irish.