Recently Solved Ciphers

I added some achievements (by me as well as by others) in 2018 in "Unsolved Historical Ciphers".

Undeciphered letters from Duke of Guise? (ca.1581)

Here are undeciphered letters to Mr de Mercoeur probably from the Duke of Guise.
I have been planning to write a background article but it will still take time. In the meantime, see
"Catalogue of Ciphers (Mainly Related to Duke of Nevers) in BnF fr.3995" for some contemporary French ciphers.
If someone achieves deciphering these, please let me know.

Undeciphered Letter to Emperor Charles V (1529)

An undeciphered letter to Emperor Charles V (24 May 1529) from Suarez de Figueroa, ambassador in Genoa is found in PARES. If someone succeeded in deciphering this, please let me know. (The strikeout on the ciphertext indicates it was deciphered at the time. A deciphered text may be found somewhare in the archives.)

I think the cipher (called the Figueroa-Charles V Cipher (1529) herein for convenience) was modelled after the Doria-Charles V Cipher (1528) (see here). If the subscript numerals consistently correspond to vowels, deciphering may not be so difficult, especially given that some word divisions are discernible.

Andrea Doria's Cipher (1528)

I updated the article "Ciphers during the Reign of Emperor Charles V" by adding a section of a cipher used by Genoese Admiral Andrea Doria in writing to Emperor Charles V.
This is the oldest vowel indicator system that I know. (Hence, I also updated "Tracing the Origin of Vowel Indicators in Spanish Ciphers" by mentioning the Doria-Charles V Cipher (1528).)

Catherine of Aragon's undecipherd letter

I found Catherine of Aragon's letter in cipher (3 November 1509) to her father, King Ferdinand of Spain, in the Spanish archives online. Unable to decipher it myself, I submitted it as a challenge at MTC3. To my pleasant surprise, two people have already solve it (which will be reflected on the MTC3 page soon). (Since the challenge is still open, I refrain from disclosing the solution.)

Since Catherine of Aragon was among the first who used cipher in the English court ("Earliest English Diplomatic Ciphers"), I have been looking for her ciphers. It is known that the Spanish archives have her letters in cipher.

For example, Catherine's first letter in cipher appears to have been that of 7 September 1507 (Bergenroth p.426), preserved in S.E.T.c.I. [i.e., Archivo General en Simancas, Estado, Tratados con Inglaterra] L.5.f.57. but I could not locate it online. Catherine's letters of the same date are found at
http://pares.mcu.es/ParesBusquedas20/catalogo/description/2208086
http://pares.mcu.es/ParesBusquedas20/catalogo/description/2208087
but these seem to be different.

As another example,
Bergenroth Suppl. p.33 has a letter originally deciphered by Almazan (20 March 1509), preserved in Archivo General de Simancas Patronato Real Tratados con Inglaterra, Legajo No.5 fo.60.


As yet another example, Catherine's letter of 29 July 1509, preserved in Britain, has a short passage in cipher (Brewer).

If any further cipher material related to Catherine of Aragon is available, please let me know.

Philip II's First Cipher (1543)

I uploaded "Philip II's First Cipher (1543)", which shows a reconstruction of Prince Philip's cipher when he was only sixteen. (Probably, the cipher was handled by a secretary.)
I also added a subsection for this cipher in "Ciphers during the Reign of Emperor Charles V".