French Ciphers at the time of the Fronde

Transcriptions of French ciphers around 1650 are given in Daniel Tant, "16 clés de déchiffrement du XVIIème siècle" (pdf). The present article briefly describes them. (The numbering no.1, no.2, ... is mine.)

The ciphers are in a bundle of Daniel de Sahuguet de Termes in the archives in Reims. He was born presumably soon after the marriage of his father in 1624 and became a captain in the regiment of M. de Fabert in 1645. The heading of no.9 (as well as the fact that no.7 and no.8 are in this collection) implies that he managed ciphers for Fabert. For some time, Sahuguet was a lieutenant of the king at Sedan. (Dictionnaire de la noblesse, contenant les genealogies (Google), Nobiliaire universel de France (Google))

Most of these ciphers consist of a homophonic substitution cipher alphabet combined with a nomenclature (code in modern parlance) for representing names, words, and occasionally syllables. Use of figures with diacritics is a characteristic also seen in a diplomatic cipher used in 1676 (see another article).

no.1 (p.4) Cipher for writing to Mr Brasvet resident for the King in Holland, received on 22 November 1650

Homophonic substitution cipher with symbols.

Code numbers 10-42, including 10-13 for cancelling the preceding character and 14-17 for nulls. Code numbers 41-99 with an overbar, 20-99 with an umlaut, and 20-92 with a circumflex cover names and alphabetically arranged words and syllables.

A, B, C, D, and E double the preceding character. M, P, Q, and R are used to surround characters to be ignored.

no.2 (p.7) Cipher that [Sahuguet] received from M. de Noirmoutier and forwarded to Marechal du Plessis on 20 August 1650, common in Raucroy [Rocroi], Charleville and Sedan

Apparently, Sahuguet received this from Noirmoutier and sent no.5 to the same at about the same time. Sahuguet appears to have been in Sedan (see above and no.7).

Noirmoutier(Wikipedia) joined the First Fronde but, after its conclusion in March 1649, was elevated to duke in March 1650 and was later alienated from the Frondeurs. He appears to have been in Charleville according to the heading of no.5 below.

Maréchal du Plessis(Wikipedia) fought for the royal cause during the Fronde. Among others, he defended Reims from Turenne and entered the town on 27 August 1650.

Substitution cipher with one- or two-digit figures. Vowels and "s" have homophones (90-95 with an umlaut, "s", "t", "u", "x", "y", "z").

The nomenclature includes figures 10-99 and letters, figures 2-99 and letters with an overbar, figures 2-99 and letters with an umlaut that cover names, words, and syllables. The arrangement is not alphabetical but syllables with the same consonant follow one another. (There seems to be an error either in the transcription or in the original because the cipher section has two-digit figures with an overbar and 2-10 without an overbar, while the nomenclature section has 2-10 with an overbar and two-digit figures without an overbar for representing single letters.)

no.3 (p.12) Cipher for "Monsieur de Roquepine et Monsieur Talon 1639", recovered in February 1650 and used for "Mr de Mons(?)"

Talon was a secretary of Cardinal de La Valette(Wikipedia) and Roquepine commanded in Metz in the absence of the cardinal around 1639 (Memoires Pour L'Histoire Du Cardinal Duc De Richelieu, vol.2 (Google), p.70, 280).

Homophonic substitution cipher with symbols, letters (often with an overbar), and figures. Special symbols defined for numerals.

Figures 5-79 represent syllables (alphabetically arranged). Figures 4-91 with an umlaut cover names (beginning with "le Roy").

Since an old code was reused, some entries were updated: "Mr le Card. De la Val." is deleted; "M. de la Valette" is replaced by "de Bouillon", "M. Talon" is replaced by "De Montagu", "Le Prince Cardinal" is replaced by "Larchiduque."

no.4 (p.15) An Unidentified Cipher

Homophonic substitution cipher with symbols, letters, and two-digit figures.

Figures 10-99 represent name (not alphabetically ordered): 38 (Le Duc Picolomini (Wikipedia)), 39 (M. de Marsin (see below)), 40 (M. de la ferté seneterre (Wikipedia)), etc. Some are nulls, some cancels the preceding letter, and some doubles the preceding letter. Figures 10-99 with an overbar represent syllables (syllables with the same consonant follow one another in alphabetical order).

"X", "u", "94", and "98" are used to surround characters to be ignored.

no.5 (p.18) Cipher sent on 17 August 1650 to Marquis de Noirmoutier in Charleville

Apparently, Sahuguet received no.2 from Noirmoutier at about the same time.

Homophonic substitution cipher with figures, letters, barred letters, and symbols.

Special symbols are defined for numerals.

Figures 23-97 represent syllables (alphabetically ordered).

Figures 4-19 with an overbar represent persons (beginning with "le Roy") and figures 4-27 with an umlaut represent place names and some words.

no.6 (p.21) Cipher for deciphering letters of Cardinal de Lavalette

Cardinal de Lavalette(Wikipedia) belongs to the time of Richelieu (see no.3).

The cipher includes two sets of substitution symbols. (The first is partially similar to no.3.)

Figures 10-84, figures 1-100 with an overbar, and letters represent names, words, and numerals.

There is also a list of some 30 words to be used to refer to different things. For example, "Verdun" means "Metz", "a midy" means "La nuit", etc.

no.7 (p.25) Cipher provided by "Duc Danguin" to M. de Marsin and [Sahuguet] in Sedan

Prince de Condé(Wikipedia) was styled "Duc d'Enghien" before the death of his father in 1646.

Marsin served under the Duc d'Enghien (Wikipedia). Considering that Sahuguet belonged to the loyal cause (judging by his correspondents), this cipher may belong to the time before the Second Fronde.

Homophonic substitution cipher with letters, symbols, and figures.

Figures 15-99, figures 1-14 with an overbar, and letters with an overbar represent words and names.

no.8 (p.27) Cipher to send to M. de Fabert for correspondence with "le Prince" [de Conde] or, in his absence, with Maréchaux (Wikipedia) de la Melleraye, de Gramont and de "Ramsan" and the court (March 1648)

Fabert had Daniel de Sahuguet (the owner of the collection) as a captain in his regiment.

Maréchal La Meilleraye (Wikipedia) was loyal to the royal cause during the Fronde. Maréchal Gramont(Wikipedia) was created Duke in 1648. Maréchal Comte de Rantzau (Wikipedia) (note the nomenclature has "Ramsau", not "Ramsan") participated in the army under the Prince of Condé in taking Ypres from Spain in April 1648 (Histoire de France sous le regne de Louis XIV, vol.1 (Google) p.284).

Homophonic substitution cipher with letters (small, capital, barred) and figures.

Figures 30-238 cover place names and generally alphabetically arranged words. Letters with an overbar represent some names.

no.9 (p.31) Cipher for M. de Fabert, sent by Maréchal du Plessis to [Sahuguet] in November 1650

Homophonic substitution cipher with figures and letters.

Special symbols are defined for some names.

Figures 44-99, figures 1-99 with an overbar, and letters represent syllables (alphabetically ordered), nulls, and names.

no.10 (p.34) General cipher with the governors of frontier towns of Picardy, Champagne, and Flanders for writing to "son Eminence" (Cardinal Mazarin?) (26 March 1650)

The Second Fronde began in January 1650, when the Prince of Condé, the Prince of Conti, and the Duke of Longueville were arrested. France was still at war with Spain (Wikipedia) after making peace with other countries in the Treaty of Westphalia in 1648. The Spanish forces in the Low Countries invaded the frontiers but peasants' resistance and the royal army in Champagne under the Maréchal du Plessis held back the invasion for the year (Wikipedia).

Homophonic substitution cipher with letters and figures.

Figures 51-266 cover place names and generally alphabetically arranged words. Letters with an overbar represent some names.

no.11 (p.38) Cipher received from Liege (30 July 1650)

Figures 1-156 and "XII" and "XIII" represent names.

no.12 (p.41) Cipher sent to M. de Remesort, "la baillé a M. de Chavigny" (31 December 1642)

Comte de Chavigny(Wikipedia) was Foreign Minister under Louis XIII and acted as messenger between the Duke of Orleans and the government.

Homophonic substitution cipher with figures, letters, and symbols.

Figures 24-95 represent names, words, and numerals.

Some of the numerals (quarante, cinquante, ..., "huitante", "nonante") are also assigned special symbols.

no.13 (p.43) Cipher that "le Pere Hasque" left for [Sahuguet] on leaving for Maastricht (20 January 1651)

Homophonic substitution cipher with figures.

Figures 12-61 with an overbar and figures 1-100 with an umlaut represent words and names.

no.14 (p.46) Cipher sent to M. de Remesort (17 June 1643)

For Remesort, see no.12.

Homophonic substitution cipher with letters (capital and small) and symbols.

Figures 1-75 represent alphabetically arranged syllables.

Figures 4-45 with an overbar represent names. Letters with an overbar represent numerals.

Figures 4-45 with an umlaut represent words.

no.15 (p.49) Cipher for "les Bocage de Dinan" (9 August 1643)

A short list of phrases to be used to mean different thing. For example, "une douzaine de grand lavé" means "mil hommes de pied."



©2018 S.Tomokiyo
First posted on 7 January 2018. Last modified on 7 January 2018.
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