It appears that even centuries ago, individuals were employing techniques to protect sensitive information. A recently decoded letter demonstrates the use of encryption to conceal royal gossip in the 15th century. ### The Decryption Process According to comments on **Bruce Schneier**'s blog, the letter was partially encrypted, with certain words omitted and multiple symbols used for the same letter. This combination of techniques made the text difficult to decode, even for modern cryptographers. ### Sophistication for the Time One commenter, **Clive Robinson**, notes that the system was fairly sophisticated for its time, effectively changing language statistics and hiding key subject indicators. This ambiguity made the letter challenging to interpret without the key. ### Lessons for Today Even today, seemingly simplistic systems can pose a challenge to attackers. The successful decryption of this medieval letter underscores the importance of understanding historical encryption methods and their potential relevance to modern security practices. ### The Voynich Manuscript Discussion also touched on the infamous Voynich manuscript, with speculation that it may be a "colour it in yourself" education book or folio, containing short-hand recordings of lectures. The high cost of vellum at the time may have contributed to the use of shorthand, but the illustrations apparently add no usable context.