[MR] BBC: Charles V's Code Broken at Last

[Garth Groff and Sally Sanford]

Noble Friends,

Today the BBC is offering a short piece on a partially coded letter written
by the Habsburg Holy Roman Emperor Charles V in 1547. Coded portions of the
letter to his ambassador at the French court, Jean de Saint-Mauris, had
until now been unreadable.

Cryptographer Cecile Pierote and her team eventually broke the code using
another Charles V letter that had been translated by its recipient (rather
careless of that officer!). The code was devilishly difficult, with vowels
indicated by diacritics as in Hebrew or Arabic, no diacritic for the very
common letter "e", single character symbols for certain people, and a few
random characters of no meaning thrown in for confusion.

The coded portions of the letter discuss a protestant rebellion in Germany
that was vexing Charles, French reaction to the recent death of Henry VIII,
and Charles' fears of assassination by an Italian mercenary. The coded text
gives instructions to the ambassador to gather information on these topics,
and how to spin them to the French. In the possible expectation the letter
would be intercepted and copied, the uncoded parts were deliberately bland
and misleading. The message provides a fascinating insight into the
political situation in Europe at that time. It also shows that in the world
of diplomacy, gentlemen do indeed read each other's mail, a claim by US
Secretary of State Henry L. Stimson after he closed down the "Black
Chamber" cryptographic office in 1929.

The BBC story is at https://www.bbc.com/news/world-europe-63757443 .

For more on Charles V, see
https://en.wikipedia.org/wiki/Charles_V,_Holy_Roman_Emperor .

Sadly, there is no Wikipedia page on Jean de Saint-Mauris.

Yours Aye,


Lord Mungo Napier, Laird of Mallard Lodge  🦆