Written by Friedrich von Junzt with the help of numerous "blood curdling and partly-suspected sources" including the surviving members of the cult of Ghatanothoa the Unaussprechlichen Kulten (Nameless Cults) or the Black Book is an occult tome published in Düsseldorf in 1839.
The pages written in the last months of his life were found in pieces with his body after his death. When his friend Alexis Ladeau managed to reassemble the fragments and read what had been written he burned them and cut his own throat with a razor.
The book was widely surpressed and after von Junzt's death in 1840 many people burned their copies. Not counting the poorly executed Bridewall translation (London, 1845) or the heavily edited reprint by Golden Goblin Press (New York, 1909) there weren't likely to be more than a half dozen copies in existance by the 1930s. One known copy can be found in the Miskatonic University Collection.
Among other topics, the book includes:
- Occult objects from around the world such as a strange monolith in the mountains Hungary. (CIRCLE: "The Black Stone", Robert E. Howard)
- A description of the prehistoric province of K'naa on the continent of Mu and the story of the High Priest T'yog. (HPL: "Out of the Aeons")
- Recreations of hieroglyphs that appeared on the carved metal cylinder in the Cabot Museum (HPL: "Out of the Aeons") and in the visions of Nathaniel Wingate Peaslee. (HPL: "The Shadow Out of Time")
- Passaged detailing a Pictish "king who rules the Dark Empire, which was a revival of an older, darker empire dating back into the Stone Age; and of the great, nameless cavern where stands the Dark Man—the image of Bran Mak Morn, carved in his likeness by a master-hand while the great king yet lived, and to which each worshipper of Bran makes a pilgrimage once in his or her lifetime. Yes, that cult lives today in the descendants of Bran's people—a silent, unknown current it flows on in the great ocean of life, waiting for the stone image of the great Bran to breathe and move with sudden life, and come from the great cavern to rebuild their lost empire." (CIRCLE: "The Children of the Night", Robert E. Howard)