Index Librorum Prohibitorum Created originally by Pope Paul IV in 1557, the infamous Index of Forbid
Index Librorum Prohibitorum Created originally by Pope Paul IV in 1557, the infamous Index of Forbidden Books is a list of books which all Roman Catholics were prohibited from reading or even owning except under special circumstances and with ecclesiastical permission. This was a very serious prohibition because those Catholics who violated it could be punished with excommunication. Books were placed on this Index because they expressed ideas which were contrary to Catholic morals, contrary to Catholic teachings, contained theological errors, or in any way posed a threat to the power of the Roman Catholic hierarchy. Enforcement of the prohibitions was given to the Sacred Congregation of the Inquisition. Updates to the Index were added regularly by either the Congregation or the Pope until its 20th edition in 1948. The Index of Forbidden Books was finally abolished in 1966 by Pope Paul VI because its existence and enforcement had become inconsistent with the growing spirit of free inquiry which had been promoted in the Second Vatican Council. It had also become quite evident that the prohibition simply wasn’t preventing Catholics from becoming aware of and even familiar with the idea that the Index was designed to suppress. image: Title page of Index Librorum Prohibitorum (Venice 1564) -- source link