Cryptologic Bytes

"On This Date in History" Calendar

1532: Hernan Cortes Letters - first known use of cryptography in New World.

Saturday, June 25, 2022

25 June 1532: A letter written by Hernán Cortés became the first known use of cryptography in the New World.

Per this excerpt from David Kahn's book, The Codebreakers: "Cortés used a small nomenclator, comprising a homophonic monalphabetic substitution, in which each letter was represented by two or three symbols, together with a few codewords for proper names."

Learn more about the Cortés letters via the Yale University Press book, Letters from Mexico via the link below. :

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