From its inception the early Christian Church sought to suppress books believed to contain heretical or erroneous teachings. With the development of the printing press during the latter half of the fifteenth century, Christian authorities in Europe became increasingly aware of the need to control the mass production of unfamiliar and potentially unacceptable texts. Initially, censorship of the press was enforced locally. However, with the spread of the Protestant Reformation, the Catholic Church required a more centralized and organized approach. Thus, the Council of Trent (1545–1563) ratified the Index librorum prohibitorum (“Index of Prohibited Books”), which listed individual banned titles as well as authors whose writings had been condemned outright. Catholic officials also published lists of expurgations, which identified specific passages to be deleted from every copy of an edition. From the sixteenth century well into the nineteenth, the censorship of books remained a primary, if not entirely effective, means of eradicating heresy and error.

It is unusual for Bridwell Library to showcase its damaged volumes. In this exhibition, however, it is necessary to focus not on handsomely preserved rare books, but on the historical evidence offered by the intentional alteration and suppression of books by Christian censors during past centuries. Of the sixty-two books and broadsides in this exhibition, thirty-seven were prohibited, enduring either physical expurgation or the threat of destruction. The remainder are publications that assisted the Church in its battle against heresy and error: several are indexes of prohibited books or expurgations, while others were written in defense of ecclesiastical censorship. Combined, the exhibited books and broadsides contribute to a fuller understanding of the role of post-publication censorship in the religious controversies of the past.