Beautiful Virgin Islands

Wednesday, Jul 23, 2025

Emperor Charles V's Secret Code Cracked After 5 Centuries

Emperor Charles V's Secret Code Cracked After 5 Centuries

Charles was one of the most powerful men of the 16th century, presiding over a vast empire that took in much of western Europe and the Americas during a reign of more than 40 years.
A team of researchers has cracked a five-century-old code which reveals a rumoured French plot to kill the Holy Roman Emperor and King of Spain Charles V.

Charles was one of the most powerful men of the 16th century, presiding over a vast empire that took in much of western Europe and the Americas during a reign of more than 40 years.

It took the team from the Loria research lab in eastern France six months to decipher the letter written in 1547 by the emperor to his ambassador in France.

The tumultuous period saw a succession of wars and tensions between Spain and France, ruled at that time by Francis I, the Renaissance ruler who brought Leonardo da Vinci from Italy.

The letter from Charles V to Jean de Saint-Mauris had languished forgotten for centuries in the collections of the Stanislas library in Nancy.

Cecile Pierrot, a cryptographer from Loria, first heard of its existence at a dinner in 2019, and after much searching was able to set eyes on it in 2021.

Bearing the signature of Charles V, it was at once mysterious and utterly incomprehensible, she told reporters on Wednesday.

'Snapshot of strategy'

In painstaking work backed by computers, Pierrot found "distinct families" of some 120 symbols used by Charles V.

"Whole words are encrypted with a single symbol" and the emperor replaced vowels coming after consonants with marks, she said, an inspiration probably coming from Arabic.

In another obstacle, he also used symbols that mean nothing to mislead any adversary trying to decipher the message.

The breakthrough came in June, when Pierrot managed to make out a phrase in the letter, and the team then cracked the code with the help of historian Camille Desenclos.

"It was painstaking and long work but there was really a breakthrough that happened in one day, where all of a sudden we had the right hypothesis," she said.

Another letter from Jean de Saint-Mauris, where the receiver had doodled a form of transcription code in the margin, also helped.

More discoveries to come

Desenclos said it was "rare as a historian to manage to read a letter that no one had managed to read for five centuries."

It "confirms the somewhat degraded state" in 1547 of relations between Francis I and Charles V, who had signed a peace treaty three years earlier, she said.

But relations were still tense between the two, with various attempts to weaken each other, she said.

So much so that one nugget of information revealed was the rumour of an assassination plot against Charles V that was said to have been brewing in France, Desenclos said.

She said "not much had been known" about the plot but it underlined the monarch's "fear".

The researchers now hope to identify other letters between the emperor and his ambassador "to have a snapshot of Charles V's strategy in Europe", she said.

"It is likely that we will make many more discoveries in the coming years," the historian said.
Newsletter

Related Articles

Beautiful Virgin Islands
0:00
0:00
Close
US Treasury Secretary Calls for Institutional Review of Federal Reserve Amid AI‑Driven Growth Expectations
UK Government Considers Dropping Demand for Apple Encryption Backdoor
Severe Flooding in South Korea Claims Lives Amid Ongoing Rescue Operations
Japanese Man Discovers Family Connection Through DNA Testing After Decades of Separation
Russia Signals Openness to Ukraine Peace Talks Amid Escalating Drone Warfare
Switzerland Implements Ban on Mammography Screening
Japanese Prime Minister Vows to Stay After Coalition Loses Upper House Majority
Pogacar Extends Dominance with Stage Fifteen Triumph at Tour de France
CEO Resigns Amid Controversy Over Relationship with HR Executive
Man Dies After Being Pulled Into MRI Machine Due to Metal Chain in New York Clinic
NVIDIA Achieves $4 Trillion Valuation Amid AI Demand
US Revokes Visas of Brazilian Corrupted Judges Amid Fake Bolsonaro Investigation
U.S. Congress Approves Rescissions Act Cutting Federal Funding for NPR and PBS
North Korea Restricts Foreign Tourist Access to New Seaside Resort
Brazil's Supreme Court Imposes Radical Restrictions on Former President Bolsonaro
Centrist Criticism of von der Leyen Resurfaces as she Survives EU Confidence Vote
Judge Criticizes DOJ Over Secrecy in Dropping Charges Against Gang Leader
Apple Closes $16.5 Billion Tax Dispute With Ireland
Von der Leyen Faces Setback Over €2 Trillion EU Budget Proposal
UK and Germany Collaborate on Global Military Equipment Sales
Trump Plans Over 10% Tariffs on African and Caribbean Nations
Flying Taxi CEO Reclaims Billionaire Status After Stock Surge
Epstein Files Deepen Republican Party Divide
Zuckerberg Faces $8 Billion Privacy Lawsuit From Meta Shareholders
FIFA Pressured to Rethink World Cup Calendar Due to Climate Change
SpaceX Nears $400 Billion Valuation With New Share Sale
Microsoft, US Lab to Use AI for Faster Nuclear Plant Licensing
Trump Walks Back Talk of Firing Fed Chair Jerome Powell
Zelensky Reshuffles Cabinet to Win Support at Home and in Washington
"Can You Hit Moscow?" Trump Asked Zelensky To Make Putin "Feel The Pain"
Irish Tech Worker Detained 100 days by US Authorities for Overstaying Visa
Dimon Warns on Fed Independence as Trump Administration Eyes Powell’s Succession
Church of England Removes 1991 Sexuality Guidelines from Clergy Selection
Superman Franchise Achieves Success with Latest Release
Hungary's Viktor Orban Rejects Agreements on Illegal Migration
Jeff Bezos Considers Purchasing Condé Nast as a Wedding Gift
Ghislaine Maxwell Says She’s Ready to Testify Before Congress on Epstein’s Criminal Empire
Bal des Pompiers: A Celebration of Community and Firefighter Culture in France
FBI Chief Kash Patel Denies Resignation Speculations Amid Epstein List Controversy
Air India Pilot’s Mental Health Records Under Scrutiny
Google Secures Windsurf AI Coding Team in $2.4 Billion Licence Deal
Jamie Dimon Warns Europe Is Losing Global Competitiveness and Flags Market Complacency
South African Police Minister Suspended Amid Organised Crime Allegations
Nvidia CEO Claims Chinese Military Reluctance to Use US AI Technology
Hong Kong Advances Digital Asset Strategy to Address Economic Challenges
Australia Rules Out Pre‑commitment of Troops, Reinforces Defence Posture Amid US‑China Tensions
Martha Wells Says Humanity Still Far from True Artificial Intelligence
Nvidia Becomes World’s First Four‑Trillion‑Dollar Company Amid AI Boom
U.S. Resumes Deportations to Third Countries After Supreme Court Ruling
Excavation Begins at Site of Mass Grave for Children at Former Irish Institution
×