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Friedrich Kasiski

Friedrich Wilhelm Kasiski, Polish by birth, spent most of his life a military man. He entered the 33rd Infantry Regiment in 1823, and over the next 29 years assumed positions from Second Lieutenant to Captain, and finally retired a Major in 1852. His commitment to national security resumed when he was made commander of a National Guard Battalion in the year 1860. He made a smooth transition from national security to information security in the year 1863, when he published a book in German titled Die Geheimschriften und die Dechiffrierkunst ("Secret writing and the Art of Deciphering").

This was the first ever written documentation of the conquering of the Vigenère cipher, even though rumor had it that Charles Babbage had arrived at a similar strategy earlier. The recorded technique was called Kasiski examination, which essentially meant analyzing gaps between repeated fragments in the text, thereby providing an indication of the key length used. But failing to receive the recognition he deserved, he forayed into archeology, spending his final years in Neustettin.

Down The Ages

• Down The Ages Home
• A Hazy Beginning
• The Political Force
  • Key Event: The Babington Plot
  • Key Event: Crypto in Latin America
  • Tools and Devices
  • People
    • Charles Babbage
    • Leon Batista Alberti
    • Blaise de Vigenère
    • Friedrich Kasiski
• The Wars