You may have heard about the fact the Inquisition banned many books, but why?Taking advantage of the Portuguese example of the Catálogo de Livros que se Proíbem Nestes Reinos, published in this country in the year of 1581, and which is essentially a local edition of the famous Index Librorum Prohibitorum, this book explores the reasons why the Inquisition forbade the reading of certain books. It provides succinct information on each of the books presented in this particular index of forbidden books, along with the probable reasons why they were forbidden to Christian audiences.