# AI decryption of historical military codes > Live situation record from CLSTR: https://clstr.news/situations/ai-decryption-of-historical-military-codes > Updated: 2026-10-03T21:00:12.000Z. Sources: 58. Developments: 3. OpenAI’s GPT-6 Astra model has demonstrated the ability to solve complex historical cryptographic puzzles. In September 2026, a developer known as “Prinz” used the model to decipher a 108-year-old German military radio message from November 1918. Using the ADFGVX cipher and the keyword “TRUPPENVERSCHIEBUNG”, the AI reconstructed text regarding British cruiser movements in Sevastopol, which aligned with historical naval logs. In October 2026, Carter Church, an engineer at the cybersecurity firm SentinelOne, utilized the same system to decrypt a 217-year-old coded letter from March 1809. The message, sent from the headquarters of Eugène de Beauharnais, Napoleon Bonaparte’s stepson, to General Auguste de Marmont, had remained unreadable due to a lost cipher key. By employing a multi-modal workflow and a technique known as “simulated annealing” to map a 1,300-character homophonic substitution cipher against known writing styles, the AI completed the decryption in approximately six hours. The process involved identifying 175 unique hand-drawn marks from a single low-resolution scan. The decoded text revealed critical military intelligence regarding French, Bavarian, Polish, and Austrian troop movements prior to war with the Habsburg Empire, including specific counts such as 40,000 Bavarians in Munich and 80,000 French troops in Bayreuth. The decryption further noted that the Russian army was marching against Austria and that the Austrian empire faced imminent attacks from multiple sides, specifically detailing the movements of the army of Friuli and strategic instructions for Marmont in Dalmatia. The breakthrough was independently verified by cryptographer Satoshi Tomokiyo, who marked the cipher as solved. ## Claims - Carter Church, an AI engineer at SentinelOne, used AI to decrypt a military letter from the Napoleonic era. (corroborated by 3 sources) - The decryption process took approximately six hours. (corroborated by 3 sources) - The 1809 letter contained secret information regarding troop movements before the war between France and Austria. (corroborated by 2 sources) - The AI used OpenAI’s GPT-6 Astra model to perform the task. (single source) - The letter was sent from Napoleon's headquarters via Eugène de Beauharnais to General Auguste de Marmont. (single source) - The decrypted text revealed the positions of Bavarian, Polish, and French forces. (single source) ## Timeline ### 2026-10-03: AI deciphers 217-year-old Napoleonic military letter OpenAI’s GPT-6 Astra model deciphered a 217-year-old Napoleonic military cipher in six hours, revealing secret 1809 troop movements intended for Marshal Auguste de Marmont. 16 sources. https://clstr.news/cluster/openai-gpt-6-astra-decrypts-napoleons-217-year-old-secret-military-letter ### 2026-10-01: AI cracks 217-year-old secret Napoleon military letter Using OpenAI’s GPT-6 Astra, engineer Carter Church decrypted a 217-year-old secret Napoleonic military letter in just six hours, revealing troop positions from 1809. 33 sources. https://clstr.news/cluster/ai-decrypts-217-year-old-napoleon-bonaparte-coded-message ### 2026-09-20: GPT-6 Astra deciphers 108-year-old WWI German military code Using OpenAI’s GPT-6 Astra, a developer has reportedly decoded a 108-year-old German WWI radio message regarding British naval movements in Sevastopol, matching historical naval records. 12 sources. https://clstr.news/cluster/ai-decodes-century-old-world-war-i-german-military-message --- Cite as: AI decryption of historical military codes. CLSTR, https://clstr.news/situations/ai-decryption-of-historical-military-codes