A letter from Rome to the abbé d'Orbais, 23 August 1589

Summary. The catalogue entry supposed that one of three keys bound in BnF fr. 3413, nos. 53, 61 and 69, might fit the letter at no. 62. None of them does. No. 53 is a numerical key and the letter has no figures. No. 61 is an Italian key with a different set of signs. No. 69 is a League key in which the square sign is e, where the letter needs n. The letter is almost all in clear. It comes from a secretary of Cardinal Pellevé in Rome, dated 23 August [1589], and carries the news of Henri III’s death. It has 91 signs of cipher, in fourteen short runs. Satoshi Tomokiyo identified the cipher as the Nevers–Piles alphabet and deciphered one name in it. His table comes from BnF fr. 3612, which is not digitised, and it is partial. It was filled out here from BnF fr. 4715 f. 2, a letter of 1586 in the same cipher whose decipherer wrote the plaintext above each line: about fifty of its words were aligned sign by sign. The decrypted runs are depeschera … dedans deux jours le doien; la protection; Mons. Cassin; vostre; Mr le […] mon maistre a esté retiré, j’ay veu ung advis qui confirme plus particulierement que nul aultre; and the signature, Baron. Extent: partial, 75 of 91 signs (82%, measured). Open: three single code signs (the first and last signs of the depeschera run, and the one after Mr le) and two short runs of six and seven signs, 16 signs in all.

01 The letter

Fr. 3413 is a Nevers-collection volume of League papers, on Gallica as btv1b52510705j. No. 62 is ff. 126r–127r (views 259–261), and the address is on f. 127v: A Monsieur, Monsieur l’Abbé d’Orbais, Con^er au Conseil estably a Paris pour la S^te Union, A Paris. The abbé d’Orbais is Jean de Piles. He was the League’s envoy to Rome earlier in 1589 and later a deputy of the clergy at the Estates of 1593.

The letter is dated only “du lieu que vous sçavez ce xxiij^e d’Aoust”, but its content fixes the year. It reports how the news of the King’s death came to Rome. A courier from Spain had passed through Lyon on the 12th. The Grand Duke of Tuscany sent an express, which reached Rome on the 20th. It carried the Duke of Lorraine’s copy of a letter of 8 August from his agent in Paris, the s^r Bardin:

le Roy a esté tué, et c’est le Roy de Navarre qui l’a faict faire, l’on a proclamé Roy a Paris Mons. le Cardinal de Bourbon, et au mesme temps le Roy de Navarre s’est aussi faict appeller Roy par ceux de sa secte

The writer apologises that his senior colleague, “son aisné de mesme charge”, has been kept from writing by a fever for a fortnight. He asks Piles to keep him in mind, and he signs in cipher.

02 The three bound keys

Each key was photographed from the Gallica scan and tested against the ciphered groups:

No.	Folio (view)	What it is	On no. 62
53	f. 109 (227)	A French key of letters to two-digit figures, with a nomenclator 1–99. Tomokiyo identifies it as Nevers collection no. 42.	Does not apply: the letter has no figures.
61	f. 125 (257)	An Italian key for the Savoy–Piedmont theatre (Birago, Saluzzo, Carmagnola…): a symbol alphabet, doubles, nulls, word signs, and a nomenclator 80–204.	Different signs. It cannot give Cassin or protection.
69	ff. 137–138 (281–284)	A French League key: a place-name nomenclator, boxed numbers, and a symbol alphabet written sideways on f. 138.	Here the square is e and there is no W, so Cassin does not come out.

BnF fr. 3413 f. 138, the symbol alphabet of key no. 69, turned upright: a to z with two or three signs each — Key no. 69, f. 138, the alphabet turned upright. It is a League key of the same period, but its square is e and its signs are not the letter’s. Image: Bibliothèque nationale de France, fr. 3413 f. 138, via Gallica (btv1b52510705j).

03 The cipher, and a key from 1586

Tomokiyo, cataloguing the Nevers ciphers, noted that no. 62 “appears to employ the Nevers–Piles Cipher” and deciphered Mons. Cassin in it. Cassin appears as Pellevé’s secretary in the proceedings of the Estates of 1593. His table for that cipher was rebuilt from Piles’s own letters to Nevers of 1586 in BnF fr. 3612. That volume is not on Gallica, and the table has gaps. It does list word signs, among them ⌘ for Mr and n for et. The same cipher is used in BnF fr. 4715 f. 2 (btv1b52509819x, view 17), the Cardinal de Guise to Nevers from Soissons, 6 October 1586. That letter is a full page of cipher, 29 lines, and the decipherer wrote the plaintext loosely above each line.

BnF fr. 4715 f. 2r, cipher lines with the 1586 decipherment written above them: encores ... nouvelles de ... qui, and Certes vous aurez subiect d'estre satisfaict de nous — Fr. 4715 f. 2r. Over the second cipher line the decipherer wrote *encores … nouvelles de … qui s’est*. Over the third, *… vous aurez subiect d’estre satisfaict de nous … Je loue Dieu … aultant de content[ement]*. Image: Bibliothèque nationale de France, fr. 4715 f. 2r, via Gallica (btv1b52509819x, view 17).

The whole page was viewed at full resolution, line by line, and about fifty words were aligned sign by sign with the writing above them (the rest of the interlinear is too cursive and abbreviated to align letter for letter). They give values the table lacks and confirm the ones it has:

Plaintext above	Signs	Values gained or confirmed
Jay receu vre	ʃ · ⊡ θ 8 y ɔ · b ⊡ æ	ʃ jay (word sign), ⊡ r, θ e, 8 c, y e, ɔ u, b v, æ e
encores	θ H W ce m x ÷	H n, W c, ce o, ÷ s
nouveles	◻ ce ◻′ φ x + y ÷	◻ n, φ v, + l
subiect d’estre	÷ b z g θ W ꝏ · 7 θ q δ m æ	z b, g i, ꝏ t, 7 d, q s, δ t
de nous	1 ⋕ ce ɔ ÷	⋕ (H with two bars)
Je loue Dieu	ẋ y · + ce ɔ θ · 3 ẋ θ ɔ	3 d, dotted x i
monde, home, chacun	∇ ce ◻ 7 θ · 4 ce ÿ y · W 4 v 8 ɔ ◻	4 h, ∇ m
pour le bien; le monde	e ʃ̄ z 9 θ ◻ · ʃ̄ ∇ m ◻ 7 θ	barred ʃ le (word sign)
qui monstrent	ε x m ◻ q …	x m, tailed m o
ou nous ferons; et a mon avis	… a θ m ce ◻ ÷ · n − ∇ ce ◻ v 9 ÷	a f, n et
de, qui	1 · ε	word signs, as in Tomokiyo’s table

A key was assembled from these values, Tomokiyo’s table and cribs from the clear context of no. 62, with the source of each value recorded (targets/orbais/decode62.py). A run counts as decrypted only when it gives French sense; letter values that give no sense are counted as open.

04 What the ciphered words say

BnF fr. 3413 f. 126v: Les jugemens de Dieu sont fort profons et inscrutables, then cipher signs, dedans deux jours, more signs, Devant cette — F. 126v. “… et inscrutables. *Ƃ 1 6 θ ÷ W 4 æ ⊡ − ʃ* dedans deux jours *Ƒ 3 tt ħ θ ◻*. Devant cette …” The first run is *[…] depeschera […]*, where 1 is the sign for de; the second is *le doien*. Image: Bibliothèque nationale de France, fr. 3413 f. 126v, via Gallica (btv1b52510705j, view 260).

Context in clear	Signs	Reading	Grade
… inscrutables. … dedans deux jours	Ƃ 1 6 θ ÷ W 4 æ ⊡ − ʃ	[Ƃ] depeschera [ʃ]	C
dedans deux jours …	Ƒ 3 tt ħ θ ◻	le doien	C
Il ne vous fault rien dire pour ce qui touche …	φ tt o V æ ʃ° ÷	open	–
Il ne fault oublier … que vous sçavez	ꝥ V 6 ⊡ m ooo θ W 8 · ɸ tt ◻	la protection	H
Mons. … detenu d’une fiebvre	W V ÷ 9 ◻	Cassin (Tomokiyo)	H
Maintenant que vous serez a … si l’histoire est vraye	ɔ tt ÷ ooo ⊡ θ · n a æ η ◻ θ	vostre [open]	H
Depuis que … a esté retiré	⌘ Ƒ τ x ⋕ ◻ ∇ V 9 · ÷ ooo ⊡ θ	Mr le [τ] mon maistre	C
a esté retiré … qui	ʃ ɔ θ φ ɔ ◻ η − 7 b ɸ q	j’ay veu ung advis	C
qui … plus particulierement que nul aultre	W ⋕ ◻ Ⱥ 9 ⊡ x æ	confirme	C
vostre tres humble servit^r … p^nte ses tres humbles recommandations	2 V ⊡ m Ħ	Baron	H

BnF fr. 3413 f. 127r: Depuis que, then a decorated square and other signs, a esté retiré, more signs, qui, more signs — F. 127r. “Depuis que *⌘ Ƒ τ x ⋕ ◻ ∇ V 9 / ÷ ooo ⊡ θ* a esté retiré *ʃ ɔ θ φ ɔ ◻ η − 7 b ɸ q* qui *W ⋕ ◻ Ⱥ 9 ⊡ x æ* plus particulierement que nul aultre.” That is: *Mr le […] mon maistre*, *j’ay veu ung advis*, *confirme*. Image: Bibliothèque nationale de France, fr. 3413 f. 127r, via Gallica (btv1b52510705j, view 261).

The passage on f. 127r decrypts to “Depuis que Mr le […] mon maistre a esté retiré, j’ay veu ung advis qui confirme plus particulierement que nul aultre”: since his master withdrew, the writer has seen a notice that confirms the news of the King’s death more precisely than any other. ⌘ is Mr in Tomokiyo’s list of word signs and Ƒ is le, as the barred ʃ is in fr. 4715 (pour le bien, le monde). The sign between them, τ, has no entry anywhere; “Cardinal”, for Pellevé, is the likely sense, but it is not counted. The run begins with ʃ, which fr. 4715 gives as jay (“ʃ receu”, Jay receu), and the next three signs give ung as in the 1586 letter. A constrained word search over a period French lexicon ranked confirme first among the candidates that make sense.

After dedans deux jours, Ƒ = le and ħ = i (Tomokiyo’s second form of i) give le doien, the dean.

The signature is the writer’s own name. In the key, 2 is b, and protection fixes the tailed m as o. The last sign is the H-form that is n in fr. 4715, so the name is Baron, not Barot. A “S^r Baron” writes in the same League dossier of 1593 as Piles (Gallica btv1b9059406b, piece u, “Du S^r Baron, du 7 aoust”). That identification is circumstantial.

The run after vostre is not regne or Champaigne, as was guessed earlier. Fr. 4715 gives n = et and a = f, which make it et f e g n e, not sense. It stays open.

05 What remains uncertain

Measured over the fourteen runs: 91 cipher signs, 75 give sense, 82.4% (before the second pass with fr. 4715, the same count gave 47 of 91, 51.6%). Grades as in the table above: H for la protection, Cassin, vostre, maistre and Baron, C for the rest. Open, 16 signs:

Ƃ, the first sign of the depeschera run: the subject of the verb (Sa Sainteté? il?). A single code sign with no entry in Tomokiyo’s table and none on the aligned part of fr. 4715.
ʃ, the last sign of the same run. It is jay elsewhere, which does not fit here.
τ, after Mr le: probably “Cardinal”, with no key entry.
“pour ce qui touche φ tt o V æ ʃ° ÷”: the known values give v o p a e ? s, not sense. Vos amis and vos gens each need a value to break.
“a vostre n a æ η ◻ θ”: et f e g n e with the fr. 4715 values, not sense.
Some values differ between the two letters. In fr. 4715, 8 is c and the plain m is r; in no. 62, protection needs 8 = t, and the tailed m is o in both. Two squares (n and u) are told apart only by small differences of form.
The rest of fr. 4715 f. 2 (lines 7, 9–11, 13, 16, 18 and 21–29) is not aligned sign by sign and might still give τ, ʃ°, Ƃ or the n–a pair. The real key source is Tomokiyo’s, BnF fr. 3612, six letters of Piles with interlinear decipherments. A new search of Gallica confirms it is not digitised; it has to be seen at the BnF.

06 Sources

BnF, fr. 3413, nos. 53, 61, 62, 69: Gallica btv1b52510705j, views 227, 257, 259–262 and 281–284. Contents from the BnF notice cc49884s.
BnF, fr. 4715, f. 2: Gallica btv1b52509819x, view 17. The aligned words are in targets/orbais/fr4715_f2_aligned.txt.
S. Tomokiyo, “Catalogue of Ciphers (Mainly Related to Duke of Nevers)”, cryptiana. See the sections on BnF fr. 3413, fr. 3612 (the Nevers–Piles table) and fr. 4715.
BnF, fr. 3612: notice cc50062c, not digitised.

The notes, the transcription of the cipher runs (no62_cipher.txt), the decoder that measures the decryption (decode62.py), the pattern-search and annealing scripts and the fetcher are in the repository (targets/orbais/). Page images are not committed.

A letter from Rome to the abbé d’Orbais, 23 August 1589