The Reformation and Counter-Reformation had a profound effect on the treatment of unchristianised peoples in Europe, intensifying efforts to convert them to Christianity, while Protestants and Catholics vied to establish their own version of the faith as the true one. The theme of paganism, intensely polemicised, occupied a central place in the religious rhetoric of the Reformation, with Protestants accusing Catholics of being little more than pagans while Catholics in turn denounced Protestants as infidels with no respect for the holy. The result was the effective reinvention of the concept of paganism, which came to be identified with folk religion (and, more specifically, folk Catholicism). ‘Paganism’ became both a greedy and a fuzzy concept, blurring the lines between those who were poorly catechised and those who were wholly unchristianised. Furthermore, ideas of infidels and idolaters formed in the New World were reimported to Europe in this period. This chapter seeks to dispel the fog of Reformation polemic in order to determine what we can know of unchristianised peoples in Europe during this period, when Orthodox Muscovy was also expanding eastward into unchristianised areas of Europe’s far east.