"On This Date in History" Calendar
1532: Hernan Cortes Letters - first known use of cryptography in New World.
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. : http://bit.ly/1iuEOyH