One of the key episodes of Michel de Montaigne's trip to Rome (1580–81) was his visit to the Vatican Library, which he comments upon in his Journal de voyage, posthumously published. Strangely enough, few scholars have paid close attention to what Montaigne says about the selection of manuscripts and printed material he consulted there on 6 March 1581. He claims that he was given free access to that Wunderkammer, and scholarly research shows that his wish list indeed reflected his taste for irony, humor, and cultural diversity, ranging from Greco-Roman manuscripts to Egyptian papyrus and a Chinese booklet. At the same time, a case could be made for interpreting the selection, not as Montaigne's, but as the library custodian's, with Aquinas's sermons, anti-Lutheran material, and documents used at the Council of Trent. This paper tries to sort out to what extent the selection of books and items that Montaigne saw at the Vatican Library can be considered as the meeting ground between the interests of Montaigne himself as skeptic and the agenda of the Counter-Reformation.