GPT-6 Astra Deciphers Napoleon's Encrypted Letter After 217 Years

An encrypted letter composed in 1809 on the orders of Napoleon Bonaparte and sent by his stepson Eugène to General Auguste de Marmont has been deciphered for the first time, according to The Daily Telegraph. The breakthrough was achieved by Carter Church, an AI engineer at a cybersecurity company, using OpenAI's GPT-6 Astra system.

The letter, written on the eve of war between France and the Habsburg Empire, contains 1,300 characters, combining letter symbols and archaic words. Because the key required for decryption had been lost long ago, its contents had remained unknown for more than two centuries. Church said he had never attempted codebreaking before and was inspired after seeing an AI model decipher a coded German message from 1941.

The message detailed the positions and strength of French and Austrian forces, and instructed Marmont to prepare his troops for marching, cautioning him not to be intimidated by small enemy forces or “a rabble.” Marmont's forces eventually broke out and helped Napoleon win the Battle of Wagram.

The report also noted that while AI has succeeded in solving mathematical problems and cracking codes, researchers worry that similar capabilities could be used to reveal the identities of anonymous internet users and leak private information.