Medieval Encrypted Letter Decoded
Sent by a Spanish diplomat. Apparently people have been working on it since it was rediscovered in 1860.
Sent by a Spanish diplomat. Apparently people have been working on it since it was rediscovered in 1860.
Clive Robinson • April 27, 2026 10:43 AM
@ Bruce, ALL,
With regards,
“Apparently people have been working on it since it was rediscovered”
It’s something Historians of all types do, be they academics, professionals, semi professionals, or hobbyists.
My Mother was a historian that due to the prejudice against women in academia back in the “inter war years” had her work stolen by male supervisors. But she still carried on doing historical research untill she died.
I got “dragged along” because I had a “keen eye for things” that most did not and I had a couple or three discoveries that I had made likewise stolen by certain academic types. Who lets be honest would not know the difference between Roman brickwork being reused and later reproductions made for the look of it, if the entire lot fell on their heads…
History still is under my skin, and I’m interested in Industrial Archaeology not just from the technology side, but the societal side of why things happened the way they did (like steam engines and boilers that exploded and spread body parts across the countryside in various states of being broiled and why it took so long to stop).
The thing is it tells much about “systems” and why things still happen almost the same way getting on for two centuries later. The technology may have changed greatly but the humans?… Not so much…
Greed and avarice are almost unchanged as are narcissistic, sadistic, psychopathic and similar “dark personality traits” even today they are regarded as incurable. As for Machiavellism and spitefulness few realise just how they are manipulated by them, along with the notion of “original sin” that underpins the “God Head” of the “King Game”.
All used as ways / excuses to control the population as a benefit for the few.
All of these things can be seen and documented, though taking things to the next stage of stopping such people almost always never happens… Terry Pratchett had a reasonably convincing if not workable theory / argument for this,
“You see, the only thing the good people are good at is overthrowing the bad people. And you’re good at that, I’ll grant you. But the trouble is it’s the only thing you’re good at. One day it’s the ringing of the bells and the casting down of the evil tyrant, and the next it’s everyone sitting around complaining that ever since the tyrant was overthrown no one’s been taking out the trash. Because the bad people know how to plan. It’s part of the specification, you might say. Every evil tyrant has a plan to rule the world. The good people don’t seem to have the knack.”
(From the Disk World novel “Guards Guards” where the Patrician Vetanari explains to the Guards leader Samuel Vimes who’s ancestor was a regicide, why tyrants or worse almost always end up in control…).
It kind of sounds better than,
“Individual Rights -v- Social Responsibilities.“
Clive Robinson • April 27, 2026 11:05 AM
@ ALL,
Questions of “why so long” in part rest on
“To prevent the information from being read by rivals, Ayala partially encrypted the letter and omitted certain words.
…
Intriguingly, Ayala sometimes used multiple symbols for the same letter, making the text even more difficult to decode.”
Along with what was in effect a partial “code book” where entire words were replaced with a single symbol.
It was a fairly sophisticated system for the time as it not only changed language statistics it hid key subject indicators. Thus making things quite ambiguous.
Even today such apparently simplistic systems can defeat quite knowledgeable or sophisticated attackers.
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Sidebar photo of Bruce Schneier by Joe MacInnis.
Anonymous • April 27, 2026 9:10 AM
Ugh, so Pedro de Ayala was basically doing 15th-century infosec, huh? Encrypting royal gossip with a bunch of goofy symbols only for it to get cracked 500 years later by some academics LARPing as codebreakers.