Blaise de Vigenère

Blaise de Vigenere ( born April 15, 1523 Saint- Pourçain, † 1596) was a French diplomat and cryptographer.

Curriculum vitae

At age 24, he worked as a secretary for the Duke of Nevers. After he died, Vigenere was commissioned in 1549 by a court to go for two years to Rome to meet diplomatic assignments there. There he first came in contact with cryptology. In 1570 he retired from the diplomatic service and devoted himself after his marriage to Marie Varé to writing, and cryptology.

He wrote more than 20 books, the most famous: Traicte de Cometes ( 1580) and Traicte de Chiffre (1585 ).

Based on the ideas of the Benedictine monk Johannes Trithemius (1462-1516), he described, among other things named after him Vigenere encryption. This was long considered unbreakable, and not until 1850, almost 300 years after Vigenere, could systematically decipher Charles Babbage Vigenere ciphers. Finally, Friedrich Wilhelm Kasiski published 1863 named after him method for determining the length of the keyword and decipherment of the algorithm.

Less well known is the autokey Vigenere encryption, which is in contrast to the Vigenere cipher, much more difficult to decipher.

• Cryptologist
• French diplomat
• Frenchman
• Born in 1523
• Died in 1596
• Man