At a glanceExisting decipherment · complete
- The letter
- Gian Giacomo Medici, marquis of Marignano, writes from Ratisbon on 12 June 1546 to Ferrante Gonzaga, governor of Milan. The letter is mostly in clear; ten lines on c. 13r are in cipher.
- Where
- Biblioteca Estense Universitaria, Modena, Autografoteca Campori, Lettera M, Medici, cc. 13–16. The record notes that c. 14 “contiene traduzione della porzione cifrata”. Not in the catalogue.
- The cipher
- A letter substitution with homophones, in signs that look like Latin letters and others. A small sigma-shaped sign is a null, and eti is a code for V. Ecc.a. Double letters are written once. Words are divided by commas and slashes.
- How it was deciphered
- This is a transcription job, not a break. The contemporary clear translation at the top of c. 14r covers the whole cipher passage, and the key was rebuilt from it.
- What it says
- The war against the Lutherans is decided. Provisions are being made, and the writer sends to Milan and Genoa for men for the artillery.
- Still open
- Three signs are doubtful, the f or sigma in two words is unsettled, and four groups of dotted vowels (nulls or stops) are not proved either way. No human palaeographer checked it, and the images were not seen here.
- Credit
- WAINUT (an AI company) transcribed the signs, rebuilt the key and read the passage with AI agents viewing the images.
01 The letter
From the imperial court at Ratisbon, Marignano tells Ferrante Gonzaga that the war against the Lutherans is decided. After the clear opening come ten lines of cipher (306 signs and groups); the letter then goes on in clear, mentioning the despatch to Milan and Genoa for men for the artillery. c. 13v carries the date and signature, and the address and the docket “Il M.se di Marignano” are on c. 14v. Below the translation on c. 14r is a clear postscript about Sebastiano de Perego, which is not part of this reading.
02 The cipher and its key
Vowels have two or more signs (for example a is j or 8). Several sign names carry two values; most are probably two similar shapes merged under one name in the transcription, and they are flagged in key.tsv. The key was rebuilt step by step from the clear translation and frozen before the final counts. The check script aligns each reading with its decryption letter by letter and fails on any departure from the signs that is not marked.
03 The reading
All 62 cipher words read as sense. 55 come verbatim from the signs and 7 carry a marked repair: four double letters restored, two doubtful signs and one sign read against its value. 59 of 62 (95.2%) have no departure from the signs other than the scribe’s single-written double letters. An independent check gives 60 of 62 (96.8%). Seven clear words in the passage are not counted. The Italian and an English translation are under Full texts.
04 What remains uncertain
- Three doubtful signs (di [?l]a, aviso [?a], and pu{b}lica, where the word is confirmed by c. 14r).
- Whether the doubtful f or sigma in actende and auctore is one or the other makes no difference to the letter value.
- The four dotted-vowel groups
{onu},{nao},{nou}and{anu}. - The transcription and key were produced by AI. No person checked them against the images, which were not seen here.
Full texts
The transcription and the decryption of every document on this page, so that the reading can be used and checked. Short files are shown here; all are in the repository.
12 June 1546, c. 13r (cipher)
From the imperial court at Ratisbon, Marignano tells Ferrante Gonzaga that the war against the Lutherans is decided. Provisions are being made and he has a large part in them; the preparation is great and he will send a detailed report by the next courier. The court professes to keep the matter secret, though it is already public; Ferrante is not to name him as the source.
Transcription
# Marignano to Ferrante Gonzaga, 12 June 1546, c. 13r: the cipher, sign by sign, after two passes and adjudication
# (validation/adjudication.tsv); M08 quale corrected 9 -> g after the independent check (3 Nov). Sign names describe shapes, not values (legend in scripts/pass2_blind.py), plus:
# H = the double-crossed sign (named # in the pass legend)
# l = a looped script l with descender (M01 only; pass 1 called it g; doubtful, written l?) s = a small sigma-shaped sign (pass 1 merged it with f)
# dd = d with a cross on the ascender W = omega (M04) as distinct from w = lying double loop (M01)
# Lo, 1o = L or a plain stroke joined to o, copied as one group ? after a sign = doubtful on the image
# {onu} {nao} {nou} {anu} = groups of dotted vowels standing apart [word] = clear word in ordinary script
# eti = a code written like a clear word (V. Ecc.a)
M01 [Qua] {onu} n j c H d o 8 , Lo & / l? 8 + u Z f s j / c H X D a 8 , n u q e a j X w
M02 , Z , T e a / k Z 9 H n D j / 9 & 8 c f Z X Lo Z / j t s e / T a H u & g e s r X Z
M03 {nao} e D , & H . X H X , n e s , h 8 X c r , Lo & / g u 8 X D H , v H dd o H
M04 Z , X e , + H , T & u , Lo & , v 8 a D Z / {nou} [Hora] 9 & c H W ,
M05 X H 9 c e a j , [meglio] . eti , [L'aparechio] , Z , + a j X Lo H ,
M06 , e , T Z a , & n , v a & o H , X Z , h 8 X 1o j a H , T 8 a D & [cular]
M07 j u & 9 H , j'? , eti , F u j 9 & N j T a H q Z dd o & H X Z Lo &
M08 D Z X e a [questa] [cosa] {anu} H c u n D 8 , g u j n Z , + & j . Z
M09 T u o? n & c j , T Z a H , eti , X H X , h & . X Z , 1 j N & j , o Z ,
M10 j u c f H a Z {nao} :Decryption
# Decryption of c. 13r, rebuilt by scripts/decode.py from transcription_c13r.txt and key.tsv.
# Per line: the signs, then the values (a|b = sign name with two values, null = no letter, ? = doubtful sign).
M01 signs {onu} n j c H d o 8 Lo & l 8 + u Z f s j c H X D a 8 n u q e a j X w
M01 values null l a c o s s|m a d i l? a g|h u|v e r|t null a c o n t r a l u|v t|f e|i r a n i
M02 signs Z T e a k Z 9 H n D j 9 & 8 c f Z X Lo Z j t s e T a H u & g e s r X Z
M02 values e p e|i r r e s o l t a s i a c r|t e n d e a l null e|i p r o u|v i s|q e|i null o n e
M03 signs {nao} e D & H X H X n e s h 8 X c r Lo & g u 8 X D H v H dd o H
M03 values null e|i t i o n o n l e|i null m a n c o d i s|q u|v a n t o p o s s|m o
M04 signs Z X e + H T & u Lo & v 8 a D Z {nou} 9 & c H W
M04 values e n e|i g|h o p i u|v d i p a r t e null s i c o g
M05 signs X H 9 c e a j eti Z + a j X Lo H
M05 values n o s c e|i r a [V. Ecc.a] e g|h r a n d o
M06 signs e T Z a & n v a & o H X Z h 8 X 1o j a H T 8 a D &
M06 values e|i p e r i l p r i s|m o n e m a n d a r o p a r t i
M07 signs j u & 9 H j' eti F u j 9 & N j T a H q Z dd o & H X Z Lo &
M07 values a u|v i s o a? [V. Ecc.a] q u|v a s i f|c a p r o t|f e s s|m i o n e d i
M08 signs D Z X e a {anu} H c u n D 8 g u j n Z + & j Z
M08 values t e n e|i r null o c u|v l t a s|q u|v a l e g|h i a e
M09 signs T u o n & c j T Z a H eti X H X h & X Z 1 j N & j o Z
M09 values p u|v s|m? l i c a p e r o [V. Ecc.a] n o n m i n e f a f|c i a s|m e
M10 signs j u c f H a Z {nao}
M10 values a u|v c r|t o r e nullReading
# Marignano to Ferrante Gonzaga, Ratisbon, 12 June 1546, c. 13r: reading of the cipher (Italian)
The cipher passage of c. 13r as the signs give it. Clear words that the writer mixed into the cipher are in *italics*.
Files: `reading_marked_c13r.txt` (line by line, checked by `scripts/check_marks.py`), `translation_c13r.md` (English),
`clear_c14r.txt` (the contemporary clear translation on c. 14r).
Marks: `(x)` = a letter with no sign, since the cipher writes double letters once. `[?x]` = a letter on a doubtful sign.
`{b}` = read b where the sign as named gives s. Null signs and the dotted-vowel groups are left out here.
*V. Ecc.a* expands the code `eti`.
## Italian
*Qua* la cossa di [?l]a guer(r)a contra luterani è per resolta, si actende al(l)e provisione, et io non li manco di quanto
posso, e ne ho più di parte. *Hora* si cognoscerà *meglio* V. Ecc.a. *L'aparechio* è grando, e per il primo ne mandarò
parti*cular* aviso [?a] V. Ecc.a. Qua si fa professione di tenir *questa cosa* oc(c)ulta, quale già è pu{b}lica. Però
V. Ecc.a non mi ne fac(c)ia me auctore.
## Notes on the text
- Spellings are the writer's and are kept: *cossa*, *di la*, *actende*, *grando*, *mandarò*, *auctore*. The translation
on c. 14r has *della*, *grande* and *autore*.
- Double letters are written once in the cipher: *guera*, *ale*, *oculta*, *facia*.
- *pu{b}lica*: the third sign is a doubtful o-like sign (`o?`). Elsewhere `o` is s or m. The word rests on the sense and
on c. 14r.
- *di [?l]a*: the l is a looped script l with a descender. It occurs once and is doubtful on the image. c. 14r has *della*.
- *aviso [?a]*: the sign is the hooked d (a) with an inner dot or stroke, which is doubtful.
- *per il primo*: by the first courier. c. 14r abbreviates it as "p.o".
- The last sentence on c. 14r reads "però V. Ecc.a no' [?mi ne] [?faccia] me autore". Some letters there are small and
doubtful.
- An earlier rough reading of that line, "no' mancarà me avisare", was wrong.Translation
# Marignano to Ferrante Gonzaga, Ratisbon, 12 June 1546, c. 13r: English translation of the cipher
Same marks as `reading_c13r.md`: `[?x]` doubtful; `{b}` read against the sign as named. "Your Excellency" expands the code
`eti` (V. Ecc.a).
Here the matter of the war against the Lutherans is resolved. Provisions are being made, and I do not fail in them as far
as I can, and I have a part in them, more than my share. Now it will be better known, Your Excellency. The preparation is
great, and by the first [courier] I will send a detailed report [?to] Your Excellency. Here they make a profession of
keeping this matter secret, which is already pu{b}lic. But let Your Excellency not make me its author [do not name me as
the source].
Notes: *si cognoscerà* is impersonal ("it will be known"). The clear translation on c. 14r runs "Hora si cognoscerà meglio
V. Ecc.a l'apparecchio è grande" with no stop, so the sentence boundary before *L'aparechio* is uncertain, and "V. Ecc.a"
may belong to either sentence. *ne ho più di parte* is rendered loosely. In *di la* (M01) the *l* stands on a doubtful sign.Key: key.tsv, key_frozen.tsv
05 Sources
- Biblioteca Estense Universitaria, Modena, Autografoteca Campori, Lettera M; IIIF manifest (CC BY-NC-SA; images not reproduced).
Working files: targets/marignano1546/ in the repository.