Unsolved Catalogue · no. 754 · class C · priority 5.0 · open

Spanish ambassadors in Genoa (Sancho de Padilla, Miguel de Oviedo, Juan de Idiáquez, Pedro de Mendoza / conde de Binasco, Juan Vivas) and García de Toledo: cipher letters and duplicates to Philip II and Philip III (1565-1603)

The densest cipher run in the sweep (about 80 items, 1571-1587 mostly): duplicates of the same letter give depth, and the series spans the 1570s-80s Italian cipher changes (see the key leads).

Date
1565-1603
Correspondents
Spanish embassy in Genoa → Philip II / Philip III, Antonio Pérez, Diego de Zúñiga
Place
Genoa
Language
Spanish
Held at
AGS, EST,LEG,1401-1432 (Génova): EST,LEG,1401,41; EST,LEG,1401,53; EST,LEG,1401,54; EST,LEG,1401,225; EST,LEG,1405,119; EST,LEG,1408,159; EST,LEG,1410,115; EST,LEG,1413,172; EST,LEG,1413,173; EST,LEG,1413,235; EST,LEG,1413,239; EST,LEG,1414,4; EST,LEG,1414,8; EST,LEG,1414,15; EST,LEG,1414,16; EST,LEG,1414,22; EST,LEG,1414,26; EST,LEG,1414,32; EST,LEG,1414,38; EST,LEG,1414,39; EST,LEG,1414,40; EST,LEG,1414,46; EST,LEG,1414,49; EST,LEG,1414,54; EST,LEG,1414,67; EST,LEG,1414,85; EST,LEG,1414,93; EST,LEG,1414,98; EST,LEG,1414,99; EST,LEG,1414,100; EST,LEG,1414,107; EST,LEG,1414,153; EST,LEG,1414,161; EST,LEG,1414,163; EST,LEG,1414,242; EST,LEG,1416,11; EST,LEG,1416,17; EST,LEG,1416,18; EST,LEG,1416,20; EST,LEG,1416,22; EST,LEG,1416,58; EST,LEG,1416,62; EST,LEG,1416,79; EST,LEG,1416,80; EST,LEG,1416,81; EST,LEG,1416,171; EST,LEG,1416,172; EST,LEG,1418,2; EST,LEG,1418,6; EST,LEG,1418,9; EST,LEG,1418,10; EST,LEG,1418,124; EST,LEG,1418,125; EST,LEG,1419,5; EST,LEG,1419,7; EST,LEG,1430,169; EST,LEG,1430,170; EST,LEG,1432,169 · 58 items; images online
Images
PARES 3550804 (EST,LEG,1401,41) · PARES 3550908 (EST,LEG,1401,53) · PARES 3550911 (EST,LEG,1401,54) · PARES 3552745 (EST,LEG,1401,225) · PARES 3661947 (EST,LEG,1405,119) · PARES 3580524 (EST,LEG,1408,159) · PARES 3577720 (EST,LEG,1410,115) · PARES 3665920 (EST,LEG,1413,172) · PARES 3665925 (EST,LEG,1413,173) · PARES 3666343 (EST,LEG,1413,235) · PARES 3666370 (EST,LEG,1413,239) · PARES 3549587 (EST,LEG,1414,4) · PARES 3550194 (EST,LEG,1414,8) · PARES 3549716 (EST,LEG,1414,15) · PARES 3549726 (EST,LEG,1414,16) · PARES 3549781 (EST,LEG,1414,22) · PARES 3549804 (EST,LEG,1414,26) · PARES 3549873 (EST,LEG,1414,32) · PARES 3549944 (EST,LEG,1414,38) · PARES 3549955 (EST,LEG,1414,39) · PARES 3550229 (EST,LEG,1414,40) · PARES 3550051 (EST,LEG,1414,46) · PARES 3550086 (EST,LEG,1414,49) · PARES 3550149 (EST,LEG,1414,54) · PARES 3550310 (EST,LEG,1414,67) · PARES 3550485 (EST,LEG,1414,85) · PARES 3550453 (EST,LEG,1414,93) · PARES 3550871 (EST,LEG,1414,98) · PARES 3550876 (EST,LEG,1414,99) · PARES 3550877 (EST,LEG,1414,100) · PARES 3550800 (EST,LEG,1414,107) · PARES 3551255 (EST,LEG,1414,153) · PARES 3551277 (EST,LEG,1414,161) · PARES 3551353 (EST,LEG,1414,163) · PARES 3552221 (EST,LEG,1414,242) · PARES 3576088 (EST,LEG,1416,11) · PARES 3576248 (EST,LEG,1416,17) · PARES 3576259 (EST,LEG,1416,18) · PARES 3576300 (EST,LEG,1416,20) · PARES 3576338 (EST,LEG,1416,22) · PARES 3578049 (EST,LEG,1416,58) · PARES 3578103 (EST,LEG,1416,62) · PARES 3578461 (EST,LEG,1416,79) · PARES 3578471 (EST,LEG,1416,80) · PARES 3578480 (EST,LEG,1416,81) · PARES 3578918 (EST,LEG,1416,171) · PARES 3578922 (EST,LEG,1416,172) · PARES 3580653 (EST,LEG,1418,2) · PARES 3580743 (EST,LEG,1418,6) · PARES 3580770 (EST,LEG,1418,9) · PARES 3580775 (EST,LEG,1418,10) · PARES 3583631 (EST,LEG,1418,124) · PARES 3583638 (EST,LEG,1418,125) · PARES 3665845 (EST,LEG,1419,5) · PARES 6706518 (EST,LEG,1419,7) · PARES 3666187 (EST,LEG,1430,169) · PARES 3666190 (EST,LEG,1430,170) · PARES 3578468 (EST,LEG,1432,169)

Hand this page to your AI agent

Give your agent (Claude, ChatGPT or any assistant that can open web pages) this address and ask it to do the task on the page:

https://dbourdeau.github.io/cyphersolver/solve/754.html

Or copy the block below into the chat. It is the whole task: what the cipher is, where the images are, what has been tried, the steps, and how to report back.

TASK: help read Unsolved Catalogue no. 754 of the cyphersolver project
This page: https://dbourdeau.github.io/cyphersolver/solve/754.html

You are helping a public research project read historical cipher letters that nobody has read yet.

THE CIPHER
  Title:          Spanish ambassadors in Genoa (Sancho de Padilla, Miguel de Oviedo, Juan de Idiáquez, Pedro de Mendoza / conde de Binasco, Juan Vivas) and García de Toledo: cipher letters and duplicates to Philip II and Philip III (1565-1603)
  Date:           1565-1603
  Correspondents: Spanish embassy in Genoa → Philip II / Philip III, Antonio Pérez, Diego de Zúñiga
  Place:          Genoa
  Language:       Spanish (expected)
  Held at:        AGS, EST,LEG,1401-1432 (Génova): EST,LEG,1401,41; EST,LEG,1401,53; EST,LEG,1401,54; EST,LEG,1401,225; EST,LEG,1405,119; EST,LEG,1408,159; EST,LEG,1410,115; EST,LEG,1413,172; EST,LEG,1413,173; EST,LEG,1413,235; EST,LEG,1413,239; EST,LEG,1414,4; EST,LEG,1414,8; EST,LEG,1414,15; EST,LEG,1414,16; EST,LEG,1414,22; EST,LEG,1414,26; EST,LEG,1414,32; EST,LEG,1414,38; EST,LEG,1414,39; EST,LEG,1414,40; EST,LEG,1414,46; EST,LEG,1414,49; EST,LEG,1414,54; EST,LEG,1414,67; EST,LEG,1414,85; EST,LEG,1414,93; EST,LEG,1414,98; EST,LEG,1414,99; EST,LEG,1414,100; EST,LEG,1414,107; EST,LEG,1414,153; EST,LEG,1414,161; EST,LEG,1414,163; EST,LEG,1414,242; EST,LEG,1416,11; EST,LEG,1416,17; EST,LEG,1416,18; EST,LEG,1416,20; EST,LEG,1416,22; EST,LEG,1416,58; EST,LEG,1416,62; EST,LEG,1416,79; EST,LEG,1416,80; EST,LEG,1416,81; EST,LEG,1416,171; EST,LEG,1416,172; EST,LEG,1418,2; EST,LEG,1418,6; EST,LEG,1418,9; EST,LEG,1418,10; EST,LEG,1418,124; EST,LEG,1418,125; EST,LEG,1419,5; EST,LEG,1419,7; EST,LEG,1430,169; EST,LEG,1430,170; EST,LEG,1432,169; 58 items; images online
  Images/records:
    - PARES 3550804 (EST,LEG,1401,41): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3550804
    - PARES 3550908 (EST,LEG,1401,53): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3550908
    - PARES 3550911 (EST,LEG,1401,54): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3550911
    - PARES 3552745 (EST,LEG,1401,225): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3552745
    - PARES 3661947 (EST,LEG,1405,119): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3661947
    - PARES 3580524 (EST,LEG,1408,159): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3580524
    - PARES 3577720 (EST,LEG,1410,115): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3577720
    - PARES 3665920 (EST,LEG,1413,172): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3665920
    - PARES 3665925 (EST,LEG,1413,173): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3665925
    - PARES 3666343 (EST,LEG,1413,235): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3666343
    - PARES 3666370 (EST,LEG,1413,239): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3666370
    - PARES 3549587 (EST,LEG,1414,4): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3549587
    - PARES 3550194 (EST,LEG,1414,8): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3550194
    - PARES 3549716 (EST,LEG,1414,15): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3549716
    - PARES 3549726 (EST,LEG,1414,16): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3549726
    - PARES 3549781 (EST,LEG,1414,22): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3549781
    - PARES 3549804 (EST,LEG,1414,26): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3549804
    - PARES 3549873 (EST,LEG,1414,32): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3549873
    - PARES 3549944 (EST,LEG,1414,38): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3549944
    - PARES 3549955 (EST,LEG,1414,39): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3549955
    - PARES 3550229 (EST,LEG,1414,40): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3550229
    - PARES 3550051 (EST,LEG,1414,46): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3550051
    - PARES 3550086 (EST,LEG,1414,49): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3550086
    - PARES 3550149 (EST,LEG,1414,54): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3550149
    - PARES 3550310 (EST,LEG,1414,67): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3550310
    - PARES 3550485 (EST,LEG,1414,85): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3550485
    - PARES 3550453 (EST,LEG,1414,93): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3550453
    - PARES 3550871 (EST,LEG,1414,98): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3550871
    - PARES 3550876 (EST,LEG,1414,99): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3550876
    - PARES 3550877 (EST,LEG,1414,100): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3550877
    - PARES 3550800 (EST,LEG,1414,107): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3550800
    - PARES 3551255 (EST,LEG,1414,153): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3551255
    - PARES 3551277 (EST,LEG,1414,161): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3551277
    - PARES 3551353 (EST,LEG,1414,163): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3551353
    - PARES 3552221 (EST,LEG,1414,242): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3552221
    - PARES 3576088 (EST,LEG,1416,11): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3576088
    - PARES 3576248 (EST,LEG,1416,17): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3576248
    - PARES 3576259 (EST,LEG,1416,18): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3576259
    - PARES 3576300 (EST,LEG,1416,20): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3576300
    - PARES 3576338 (EST,LEG,1416,22): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3576338
    - PARES 3578049 (EST,LEG,1416,58): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3578049
    - PARES 3578103 (EST,LEG,1416,62): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3578103
    - PARES 3578461 (EST,LEG,1416,79): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3578461
    - PARES 3578471 (EST,LEG,1416,80): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3578471
    - PARES 3578480 (EST,LEG,1416,81): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3578480
    - PARES 3578918 (EST,LEG,1416,171): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3578918
    - PARES 3578922 (EST,LEG,1416,172): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3578922
    - PARES 3580653 (EST,LEG,1418,2): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3580653
    - PARES 3580743 (EST,LEG,1418,6): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3580743
    - PARES 3580770 (EST,LEG,1418,9): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3580770
    - PARES 3580775 (EST,LEG,1418,10): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3580775
    - PARES 3583631 (EST,LEG,1418,124): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3583631
    - PARES 3583638 (EST,LEG,1418,125): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3583638
    - PARES 3665845 (EST,LEG,1419,5): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3665845
    - PARES 6706518 (EST,LEG,1419,7): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/6706518
    - PARES 3666187 (EST,LEG,1430,169): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3666187
    - PARES 3666190 (EST,LEG,1430,170): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3666190
    - PARES 3578468 (EST,LEG,1432,169): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3578468

WHAT IS KNOWN
  Status: PARES hits (27 Oct 2026, "carta cifrada"/"cifrada"; EST,LEG,1401,54, 1416,11 and 1416,79 also "no descifrada"). Pairs of "Carta cifrada" and "Duplicado de carta cifrada" of the same letter are common (e.g. 1414, 1416). PARES full-text search matches words, not the phrase, so a term hit is a pointer; the hit-list title says the letter is in cipher, not whether a decipherment is filed with it. Sibling of the Binasco 1592 row already here (EST,LEG,1424,79). EST,LEG,1394,247 (PARES 3576569, García de Toledo to Philip II, 16 July 1565), found in the sweep, is targets/toledo1565/, already solved, and was taken out of this row at the merge review (27 Oct 2026); its key (two-digit homophonic, 12-43) is the first to try on the García de Toledo items here. known.py missed it because the repo writes "AGS Estado leg. 1394 no. 247", not "EST,LEG,1394,247"; re-run with "leg. 1401/1405/1408/1410/1413/1414/1416/1418/1419/1430/1432": no other hits for the remaining legajos (checked 27 Oct 2026).
  Outcome so far: not yet attempted by the project
  Prior-art check: not searched (title screening only). Check first: Estudios Románicos 34 (2025) and Luo (2021) for 16th-century AGS Estado ciphers; Tomokiyo, cryptiana, for Philip II Italian ciphers; CODOIN prints some Genoa despatches.
  Check first: Try the toledo1565 key (two-digit homophonic, 12-43) on the García de Toledo items first. Open the three "no descifrada" hits (1401,54; 1416,11; 1416,79); then sample the run for filed descifrados.
  Class C: no key and no deciphered sibling is known, so expect a ciphertext-only attack.
  Project notes (read these before anything else; they record what was tried and ruled out): https://github.com/dbourdeau/cyphersolver/blob/main/targets/toledo1565/NOTES.md

STEPS
0. Set up. If you can run a shell, fork and clone the repository and work inside it:
     git clone https://github.com/dbourdeau/cyphersolver.git
   Then read, in this order: CONTRIBUTING.md (how a contribution is sent and credited); README.md, sections
   "Repository layout" and "Conventions" (how readings are measured and named); targets/toledo1565/NOTES.md (everything
   already tried on this cipher, with the files it used); and lang/README.md (shared language models).
   Put all your work in targets/toledo1565/: transcription, key, decipherment, scripts. Add your findings to its NOTES.md
   under a dated heading, without rewriting what is there. Keep WORKLOG.md there too:
   one dated line per step (transcription, hypothesis, solver run, crib, key found, control), failures included.
   Do not edit docs/ (the site is generated and rebuilt on merge) and do not commit large images: link them.
   If you cannot run a shell, do the same work in files you keep and send them with the issue below.
1. Make sure it is still unread. Search the web and the literature for the shelfmark, the correspondents and the date:
   printed editions and calendars of the correspondence, Satoshi Tomokiyo's cryptiana pages
   (https://cryptiana.web.fc2.com/), the DECODE record and the files attached to it, and the project notes above.
   If a decipherment already exists, stop and report where it is. That is a useful result.
2. Get the images. For Gallica items, a page image is
   https://gallica.bnf.fr/iiif/ark:/12148/<ark>/f<page>/full/full/0/native.jpg (page numbers from the manifest).
   DECODE records (de-crypt.org) need a free account: if you cannot log in, ask your human to download the images for you.
3. Look for key material before attacking the ciphertext, in this order: a decipherment written between the lines or
   in the margin; a clear copy or a deciphered sibling letter in the same volume or DECODE series; a key sheet from the
   same office and years (DECODE key records, Tomokiyo's articles, printed editions); clear passages in the letter
   itself that can serve as a crib.
4. Transcribe exactly what is on the page: one token per sign or number group, line by line, with folio and line
   numbers, unclear signs marked with ?. Keep the transcription as a file. It is worth sending even if nothing else works.
5. If no key exists, identify the system (count the distinct symbols, tokens and repeats: simple or homophonic
   substitution, nomenclator with code words, syllabary, two-digit figures) and recover the key from the ciphertext
   with a solver scored on a language model of the period (Spanish). In the clone, use the shared models in lang/
   (from lang import lm; lm.load('<model>'), lm.best_language(text)) rather than building your own; add a corpus there
   if none fits. Before trusting a result, run the same solver on a control text you encipher yourself in the same
   system and at the same length. If it cannot solve the control, its output on the real letter means nothing.
6. Measure the result against the project's bar (README.md, Conventions). A text is "complete" only when (1) at least
   95% of its cipher tokens give sense, counted from a reading file, not estimated; (2) no gap is left untried;
   (3) every letter in the item is covered; (4) what stays open is scattered code groups or names, or pieces blocked
   from outside (no key material, too short, illegible, needs the archive). Otherwise it is "partial": say which
   pieces are open and why. Mark every uncertain word with [?] and leave unread groups as their numbers or signs.
   Never fill gaps with plausible guesses. A failed attempt that records what was ruled out is still a contribution.
7. Name how the text was obtained with one of the project's methods (do not write just "solved" or "read"):
     - ciphertext-only break: The key was rebuilt from the ciphertext alone: frequencies, solvers, pattern words, the order of the key. No plaintext and no existing key was used. If someone had solved the same text earlier and it was found only afterwards, the write-up says so: an independent re-solution.
     - key from external plaintext: The key was rebuilt by matching the ciphertext against a plaintext found elsewhere: a printed edition, a calendar of state papers, a copy of the same letter in another archive.
     - key from adjacent plaintext: The key was rebuilt from plaintext next to the ciphertext: a partial decipherment written between the lines or in the margin, clear passages in the same letter, a deciphered copy in the same file.
     - external key matched: An existing key that had not been connected with this document (a key for another correspondent or series, a key sheet filed elsewhere) was found to fit, and applied.
     - known key applied: The key was already identified for this document or its correspondence (on its archive or DECODE record, published for it, filed with it) and was applied. The work is transcription and decipherment, which is not mechanical when the key is polyphonic or variable-length.
     - existing decipherment: A complete decipherment already existed (between the lines, on a separate copy, or in print). The work was transcribing the cipher and checking the decipherment against it.
     - not solved: Attempted; neither the key nor the text was obtained. What was learned is recorded. A target whose key was obtained but whose text does not read keeps the method that obtained the key, with extent "none (text not read)".
     - not applicable: Not a cipher (clear text, shorthand, a key sheet, instructions), or the item could not be reached.

REPORT BACK
With a clone: open a pull request with your targets/toledo1565/ folder. Say in the description how you want to be
  credited (name, initials or handle, and a link) and include the same points as the issue below.
Without one: open an issue: https://github.com/dbourdeau/cyphersolver/issues/new?template=solution.yml&title=Solution%3A+catalogue+754&target=catalogue+754
(other kinds of contribution: https://github.com/dbourdeau/cyphersolver/issues/new/choose). Include:
  - Target: catalogue 754
  - the documents and the images you worked from;
  - the key: sign-to-value table, code groups with values, nulls;
  - the decipherment line by line against the ciphertext, with uncertain passages marked;
  - the method (step 7), the share of tokens that give sense, complete or partial (step 6), and whether the
    reading was already published anywhere;
  - your step log (WORKLOG.md), and the tools and the AI model you used.
If you cannot open issues or pull requests, write this report for your human to send. Credit goes to the person who sends it.

Where the cipher is

Cipher located and confirmed. 3 of 58 items viewed: 3550804 images 1-4 (EST,LEG,1401,41); 3550908 images 1-4 (1401,53); 3550911 images 1-4 (1401,54): All three opened items are Genoa letters of Nov-Dec 1571 signed by Sancho de Padilla to Philip II, each with a full cipher body and clear dateline and signature: 3550804 (1401,41, 6 images, sampled 1, 3, 4, 6): about 25 lines of mixed figure/sign cipher (15, 16, 8, 13 with overbars and strokes) with clear docket 'Genoua Sancho de Padilla 1571' on image 3; 3550908 (1401,53, 9 Nov 1571): about 34 lines on image 1, 30 on image 2, a dozen on image 3, same cipher and clear closing; 3550911 (1401,54, 5 Nov 1571): about 25 lines on image 1 and 25 on image 2, same cipher, clear closing. No decipherment or gloss on any page seen; the docket on the verso of 1401,54 is a short heading only. Spanish. (checked 2026-11-02 by an LLM on the page) open that page

What is known

Status and prior art. PARES hits (27 Oct 2026, "carta cifrada"/"cifrada"; EST,LEG,1401,54, 1416,11 and 1416,79 also "no descifrada"). Pairs of "Carta cifrada" and "Duplicado de carta cifrada" of the same letter are common (e.g. 1414, 1416). PARES full-text search matches words, not the phrase, so a term hit is a pointer; the hit-list title says the letter is in cipher, not whether a decipherment is filed with it. Sibling of the Binasco 1592 row already here (EST,LEG,1424,79). EST,LEG,1394,247 (PARES 3576569, García de Toledo to Philip II, 16 July 1565), found in the sweep, is targets/toledo1565/, already solved, and was taken out of this row at the merge review (27 Oct 2026); its key (two-digit homophonic, 12-43) is the first to try on the García de Toledo items here. known.py missed it because the repo writes "AGS Estado leg. 1394 no. 247", not "EST,LEG,1394,247"; re-run with "leg. 1401/1405/1408/1410/1413/1414/1416/1418/1419/1430/1432": no other hits for the remaining legajos (checked 27 Oct 2026).

Outcome so far. Not yet attempted by the project. Prior-art check: not searched (title screening only). Check first: Estudios Románicos 34 (2025) and Luo (2021) for 16th-century AGS Estado ciphers; Tomokiyo, cryptiana, for Philip II Italian ciphers; CODOIN prints some Genoa despatches..

Check first. Try the toledo1565 key (two-digit homophonic, 12-43) on the García de Toledo items first. Open the three "no descifrada" hits (1401,54; 1416,11; 1416,79); then sample the run for filed descifrados.

Scores

Importance
3 of 5
Solvability
3 of 5
Difficulty
3 of 5
Class C
no key and no deciphered sibling is known, so expect a ciphertext-only attack
Note
Scored from the PARES hit list (title, dates, signatura only) during the 27 Oct 2026 PARES batch (research/pares_ags/, screen.py + reading of the top of screen_ranked.tsv); full description and images not viewed

Send a result

A reading, a partial reading, a transcription, or a source that shows it was read long ago: all of it counts and is credited to you on the site.

Open a solution issueOther kinds of reportHow credit works← All unsolved ciphers