De Umbrarum Regni Novem Partis
A book written and printed by Aristide Torchia in 17th Century Venice. Torchia was apparently a very competent master of the bookmaker’s art, but not as wise in political matters. He was burnt at the stake for his Satanism along with all but three copies of his book in AD 1667. One of the mysteries surrounding the book is the fact that he only claimed one more existed under interrogation by the Inquisition.
The reason the holy office was so darn upset by the book was that it described in great detail the advantages of supporting Satan in his war with god. It also contained an encoded formula for how to summon the Devil.
While burning Torchia is said to have remained alive an unnaturally long time and prayed looking towards the earth. It is also rumored that Lucifer himself aided him during the printing of the book in addition to having inspired its creation.
The secrets of the The Nine Gates are an important part in both El Club Dumas (The Club Dumas) by Arturo Pérez-Reverte and the movie based upon that tale, The Ninth Gate. It is currently unknown if there is any truth to the destruction of the remaining three tomes as related in the story or it was merely a fiction.