Steganographia is a book on steganography, written in c. 1499 by the German Benedictine abbot and polymath Johannes Trithemius.

Trithemius' most famous work, Steganographia (written c.1499; published Frankfurt, 1606), was placed on the Index Librorum Prohibitorum in 1609[1] and removed in 1900.

[3][4] References within the third book to magical works by such figures as Agrippa and John Dee still lend credence to the idea of a mystic-magical foundation of the third volume.

[5][6] Additionally, while Trithemius's steganographic methods can be established to be free of the need for angelic–astrological mediation, an underlying theological motive for their contrivance remains.

The preface to Polygraphia equally establishes the everyday practicability of cryptography, and was conceived by Trithemius as a "secular consequent of the ability of a soul specially empowered by God to reach, by magical means, from earth to Heaven".