Cryptologic Bytes

22 May 1881: Death of Friedrich Wilhelm Kasiski, a German infantry officer and cryptographer who developed a solution for polyalphabetic cipher. In 1863, Kasiski published a 95-page book on cryptography, Die Geheimschriften und die Dechiffrir-Kunst (German, "Secret writing and the Art of Deciphering"). This was the first published account of a procedure for attacking polyalphabetic substitution ciphers, especially the Vigenère cipher. In 2013, the NCMF was fortunate to obtain a copy of Kasiski's very rare 1863 German language book on cryptology from a private European seller. LEARN MORE.

The significance of Kasiski's cryptanalytic work was not widely realized at the time. Cryptologic historian Dr. David Kahn notes, "Kasiski died on May 22, 1881, almost certainly without realizing that he had wrought a revolution in cryptology." (The Codebreakers)