During the American Revolutionary war, a book cipher was used between Frederick Haldimand, Governor in Quebec, and Sir Henry Clinton, Commander-in-Chief in New York. It is described in a new article, "Haldimand-Clinton Book Cipher (1778-1782)".
It appears that the book cipher was also applied in letters from Lord Germain. It is wondered whether ciphers had not been used in trans-Atlantic communication. British ciphers during the Revolutionary War are also outlined.
AGS (Archivo General de Simancas) Est. Leg. 1.1.1 is a collection of 238 ciphers from various times. Regrettably, these ciphers are not organized or properly labelled, as I hear.
The other day, I learned in Pich-Ponce (2024) (see here for citation) that Claudio Pérez y Gredilla compiled ciphers in AGS in "El Libro de cifras" (AGS D/203). According to Otto Vervaart's blog, it is an unpublished manuscript and deals with about 200 ciphers. (I guess AGS Est. Leg. 1.1.1 is its major scope.)
Perhaps Benavent (2025) refers to the same manuscript by "El estudio de la claves" written by Claudio Pérez y Gredilla, an official of the archives. She tells this essay was even favourably reviewed for publication by Antonio Rodríguez Villa in Boletín de la Real Academia de la Historia.
A list of Rodriguez Villa's papers at Biblioteca Virtual includes the review:
Rodríguez Villa, "Cifra diplomática", Boletín de la Real Academia de la Historia, tomo 24 (1894), p.108-109 (bibliography, text). (It shows that Claudio Pérez y Gredilla was head of AGS and the title given by Benavent is correct.)
Benavent says it is not certain whether Claudio Pérez y Gredilla's essay was ever printed. Given that it is at least not easily accessible now, I hope someone publishes its edition somewhere. (For example, Cryptologia accepts "From the Archives" pieces.)
When I called for a match for unsolved Charles V's ciphers in a collection of ciphers from 1521-1527, George Lasry immediately responded with solutions produced by his solver. I now added a section for these in an article for his achievements. As it turned out, I already posted his solution to one back in 2023 but I was not aware of it in writing the last blogpost. (The solutions still require attention of someone versed in Spanish.)
This adds two more ciphers to the collection of Charles V's ciphers from 1521-1527 in Kolosova (2017) I introduced here.
It is interesting that the Marquis of Gasto (Guasto, Vasto) used different ciphers in writing to the Emperor in September and November 1527.
Three ciphers used in letters to/from Charles V remain unsolved ("Unsolved Historical Ciphers"):
- Letter from Emperor Charles V (1521?): BnF Clair. 322, f.105v (Gallica)
- A Report to Charles V (1527?): BnF fr.3022, f.16 (Gallica)
- Marquis of Gasto to Charles V (1527). ff.26-28, 39, 40-43 (Gallica)
When I came to know 17 ciphers reconstructed by Olga Kolosova from letters to Charles V in 1521-1527 ("Scholarly Studies on Ciphers in the Reign of Emperor Charles V"), I was thrilled because the scope exactly matched these unsolved ciphers. But I couldn't find a mathing cipher among her reconstructions. It may well have been that the three ciphers are simply not among the 17 reconstructions, but I have to admit my search was not thorough. I simply looked for a couple of symbols in each cipher (e.g., "3" with an additional stroke below in BnF fr.3022, f.16; "s", "3", "v" with two additional lines in BnF fr.3022, f.26). Although this worked for Mary-Grange Cipher (1571) (see here), there's some chance that I simply overlooked this time. If someone finds a match, please let me know.
When working on some recent posts, I noticed there has been active research about ciphers in the time of Emperor Charles V in the past few years. I outlined them in a new article, "Scholarly Studies on Ciphers in the Reign of Emperor Charles V" with some observations from cryptographer's perspective.
Most of the many ciphers reconstructed by scholars from archival materials are not covered in my article, "Ciphers during the Reign of Emperor Charles V", while my article also has some not covered by their work. In a few cases where we work on the same cipher, independent reconstructions will supplement each other.
