Index librorum prohibitorum

List of books considered dangerous to the faith or morals of Catholics. Compiled by official Roman Catholic censors, the Index was never a complete catalog of forbidden reading; it contained only works that the ecclesiastical authority was asked to act on. Though the church's concern over books is much older, the first catalog of banned books to be called an index was published in 1559. Publication of the list ceased in 1966, and it was relegated to the status of a historic document.