# AI Used to Decrypt Medieval Ciphers

> Source: <https://www.schneier.com/blog/archives/2026/06/ai-used-to-decrypt-medieval-ciphers.html>
> Published: 2026-06-03 11:04:40+00:00

## AI Used to Decrypt Medieval Ciphers

Researchers are using machine learning algorithms to [decrypt](https://www.bbc.com/future/article/20260527-plots-love-letters-and-diplomacy-the-medieval-secrets-being-revealed-by-ai) historical pencil-and-paper ciphers.

Researchers are using machine learning algorithms to [decrypt](https://www.bbc.com/future/article/20260527-plots-love-letters-and-diplomacy-the-medieval-secrets-being-revealed-by-ai) historical pencil-and-paper ciphers.

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