The Founding Fathers Encrypted Secret Messages, Too

As a youth in the Virginia colony, Thomas Jefferson encrypted letters to a confidante about the woman he loved. While serving as the third president of the newly formed United States, he tried to institute an impossibly difficult cipher for communications about the Louisiana Purchase. He even designed an intricate mechanical system for coding text that was more than a century ahead of its time.

Cryptography was no parlor game for the idle classes, but a serious business for revolutionary-era statesmen who, like today’s politicians and spies, needed to conduct their business using secure messaging. Codes and ciphers involving rearranged letters, number substitutions, and other now-quaint methods were the WhatsApp, Signal, and PGP keys of the era.