Index Librorum Prohibitorum

Pius IV (b. 1499, r. 1559–1565).
Index librorum prohibitorum, cum regulis confectis per patres a Tridentina Synodo delectos, auctoritate sanctiss. D.N. Pii IIII, Pont. Max. comprobatus.
Rome: Paulus Manutius, 1564. (ACY3341)

The Index librorum prohibitorum (“Index of Prohibited Books”) was a direct outcome of the Council of Trent. In 1546, the fourth Tridentine session determined which books of the Latin Bible were canonical and decreed that only the Catholic Church was authorized to interpret Scripture. In 1562, the eighteenth session mandated that a special conciliar commission would examine the growing problem of heretical literature. The Council’s action resulted in the publication of the first Tridentine Index librorum prohibitorum in 1564. Although preceded by Spanish indexes beginning in 1551 and the Pauline Index published in Rome in 1559, the Tridentine Index, backed by the authority of the Council of Trent, initiated four centuries of rigorous censorial control within Catholic realms.

The first Tridentine Index prohibited the complete writings of 610 authors, identified 69 additional authors whose prohibited works were listed individually, and banned 297 anonymous titles. As would be the case with all indexes of prohibited books, no explanation was provided for a text’s suppression. Owned by an unidentified Spanish nobleman in the later sixteenth century, Bridwell Library’s copy of the first edition is bound with a contemporary handwritten Spanish translation of the collected decrees of sessions 17 through 25 of the Council of Trent.