Pope Gregory XIII

(1502 - 1585)

Born Ugo Buoncompagni, Gregory assumed the papacy in 1572. Ten years later he reformed the Julian calendar in order to reliably calculate the date of Easter. The change was regarded by many Protestants as the work of the Antichrist, aimed at inflicting the devil’s power upon the earth. Michel de Montaigne wrote that the pope troubled “himself very little about politics, but a great deal about building, in which particular he will leave, at Rome and elsewhere, memorials greatly redounding to his honor.”