Charles VI to Windischgrätz (1720–1722)

Summary. DECODE catalogues six records of letters from the Emperor Charles VI to Count Leopold Viktorin Windischgrätz, his envoy at The Hague and later his plenipotentiary at the Congress of Cambrai, as non-decrypted. They are four letters, two of them surviving both in the autograph and in the family’s fair copy. The records themselves name the keys: R5017, the old key with the secret Court Chancellery, and R5018, the private key that the first letter announces. Both keys were transcribed in full from the DECODE images and applied without any reconstruction, and every cipher passage reads as German that fits its clear-text context. 3 February 1720: with Alberoni just expelled from Spain, the Emperor fears France may make a separate peace with “the Duc d’Anjou” (Philip V) through Morville. Windischgrätz is to confide in Cadogan, cultivate Portugal and bring it into the Alliance, and refuse any change to the treaty; Sardinia for the Duke of Lorraine is “sehr ideal”, and the Emperor insists on the equivalent for Montferrat. 13 April 1720: Spain and Orléans, and the burden of the Dutch Barrier. 24 July 1720: Beretti Landi proposes a marriage between one of the Emperor’s children and Philip V’s sons, but “they are both so small”. 11 April 1722: Beretti again, and the Spanish marriage. Jakub Mírka described the letters and keys in 2012 but printed no decipherment. Status: all cipher passages read. Two nomenclator cells in the first letter are uncertain, and the clear text of the later letters is summarised rather than edited.

01 The letters and the two keys

The letters are autograph notes that Charles VI sent through his Oberststallmeister, outside the Chancellery’s ordinary despatches. The family later copied them into a register (book 5 of inv. 5), numbering them No. 1 to No. 7. DECODE has four of them:

No.	Date	DECODE	Key	Cipher
1	Vienna, 3 Feb 1720	R5019 (autograph), R5020 (copy, pp. 401–404)	R5017	26 passages, about 190 groups
2	Vienna, 13 Apr 1720	R5021 (autograph), R5022 (copy, pp. 404–407)	R5018	2 passages
3	Vienna, 24 Jul 1720	R5023 (copy, pp. 407–409)	R5018	3 passages
6	Vienna, 11 Apr 1722	R5024 (copy, pp. 414–416)	R5018	4 passages

R5017 is headed Ziffer Schlüssel mit der geheimen Hof-Canzley. It is the deciphering half of a two-part nomenclator. The numbers 1–400 are a scrambled syllabary of letters, bigrams and a few trigrams (schli, stre, spra), plus nulls (errans), punctuation and the controls annulla praecedentia / sequentia. The numbers 401–977 are words and names in alphabetical order, from Aachen to zu: 458 Cadagan, 513 Duc d’Anjou, 657 Mr. Moroille, 749 D. Orleans, 814 Robethon, 819 Stanhop. R5018 is the new private key, on a single sheet. Each of 24 letters has a number from 10 to 38 and a graphic sign, and the vowels have a second number. About 300 codes follow, as numbers 39–210 or two-letter groups (ab Anjou, fb Spanien, zi Hof, 69 Beretti Landi, 151 Oesterreich, 159 Orleans), and the nulls are 3 4 5 6 7 9. Several names were added later in paler ink, among them Fleury, Walpole and Windischgrätz himself. In the first letter the Emperor writes that “den Ziffer, so ihr mit mir zu brauchen” would follow; the later letters are all in R5018, as Mírka noted.

The alphabet grid at the top of key R5018: letters A to Z, each with a number and a graphic sign — Key R5018, the top of the sheet: each letter with its number, its sign and, for the vowels, a second number. The nomenclature columns begin below.

02 No. 1, 3 February 1720: Alberoni, France and the peace terms

The letter is two-thirds clear German, written in Charles’s own phonetic hand. The cipher sits inside the sentences, as in “absonderlich 89 312 251 65 14 312 20 48 96 genau berichten” = den Pentenrider. The autograph and the copy agree group for group. The 26 passages, in order:

Register copy, page 402: clear German with runs of cipher numbers — Register copy, book 5 p. 402: “absonderlich *den Pentenrider* genau berichten, alles was ihr nur werdt oder geringsten *Argwohn machen von Frankreich und dem Regenten*”.

	Clear text before	Cipher reads
A	absonderlich	den Pentenrider (genau berichten)
B	oder geringsten	Argwohn machen von Frankreich und dem Regenten
C	auch wohl	mit dem Cadagan confident eröffnet
D	aber auf keine weis	gegen dem Frankreich auch kein geringsten Argwohn
E	absonderlich	da nun der Alberoni aus Spannien abgeschafft
F	(bracket)	zu fürchten, dass Frankreich vielleicht suche mit Duc d’Anjou ein sonder Frieden zum Mr. Morville
G	auf seiner hut, doch	ohne einichen geringsten Argwohn
H	gut vernemen und vertrauen	mit dem Graf Daroqui [Tarouca]
I	finden wir ohne dem schon	von Portugal aus (sein gute Neigung)
J–L	…	sein König … der Allianz · publico kein mehreren darum · (als) seinen König in die Allianz (zu bringen)
M	auf das obige aber mich	Portugal denken
N	das wird nicht wohl	sein, [eh er] mesuren nimbt und Beytritt [446] ein von Spanien untertruckt
O	werdet ihr	Cadogan (auf all weis suchen beyzuhalten)
P	Unbilligkeit so wohl als schaden	aller Alliirten, ja Engelländer selbst
Q	man	in künfftigen Frieden
R	nur das geringste wider	die zwischen uns gemachte Tractat geändert würde
S	das under wegen	Sardinien dem Herzog von Lothringen (zu geben ist sehr ideal und nicht wohl thunlich)
T	endlich auch	wie der dem guten Glauben der Tractaten
U	das sonst	mir das Aequivalent von Montferrat
V–W	das in · den	künfftigen Frieden (dieses onus nicht auf mich fall) · dem Duc d’Anjou
X	oder dem so	gross zu [638] dem Nutzen
Y–Z	ob (wie wohl endlich zu glauben)	D. Orleans … denke mit dem Duc d’Anjou ein particular Frieden zu machen

So the secret instructions are these. Keep Pentenriedter fully informed, confide in the British envoy Cadogan, and show France and the Regent no mistrust. Watch them all the same: now that Alberoni has fallen, France may look for a separate peace with Philip V (whom Vienna still called only “the Duc d’Anjou”) through Morville, the French minister at The Hague. Find out whether Orléans means to make one. Win over the Portuguese envoy and bring his king into the Alliance. On the peace terms, nothing in the Quadruple Alliance treaty is to change: Sardinia for Lorraine is impracticable, the Montferrat equivalent is owed, and the costs of the coming peace must not fall on the Emperor.

03 Nos. 2, 3 and 6 in the private key

In R5018 the letters are spelt out one symbol at a time, mixing the number and the sign for the same letter freely, and names are given as codes. Read from the register copy:

Register copy, page 408: cipher in numbers and graphic signs — Register copy, book 5 p. 408 (No. 3): “Was nemblich *der Beretti Landi euch Namen* seines *Hofs* über *ein Proposition* gethan eine *Heyrath zwischen* ein oder andern *meiner Kinder* und *Anjou Söhne*”.

No. 2, 13 April 1720. “Das ob und Orleans sich endlich wider miteinander verstehen werden, ist schir zu besorgen”; and a project for how one might free oneself entirely “von dem onere der Barriere”, the Emperor’s cost of the Dutch garrisons in the Barrier fortresses.
No. 3, 24 July 1720. The Spanish envoy Beretti Landi, in the name of his court, has proposed “eine Heyrath zwischen ein oder andern meiner Kinder und Anjou Söhne”. Charles would stay “in guter Verstendnus mit seinen Hof”, but as for die Heyrath, “weren beede so klein” that nothing should yet be made known. His eldest daughter, Maria Theresa, was three.
No. 6, 11 April 1722, to Windischgrätz as plenipotentiary at Cambrai, opening with the Emperor’s grief at the death of his Oberststallmeister. The cipher covers what he writes “wegen des Beretti”, especially what he discussed “mit Beretti wegen einer Heyrath” between “Spanien und mir”. Beretti is “erbittert wider mich und Oesterreich”, yet it is not bad “sich des Beretti zu gebrauchen” and to show “ihm all Convenienz in utili et honorifico”.

The marriage theme runs from 1720 to 1722, well before the Ripperda negotiations of 1725 that promised the Emperor’s daughters to Philip V’s sons.

04 Method

The records were fetched from DECODE with the project’s logged-in cookie. The R5017 syllabary (1–400) was read column by column from the full-resolution scan. The nomenclator (401–999) and the whole of R5018 were transcribed from tiled crops, with a confidence mark on each cell. The ciphertext of No. 1 was taken from the copy, checked against the autograph, and decoded by a short script (dec.py). The letters in R5018 were decoded by hand, because the copyist’s signs have to be matched to the key’s drawings. Two slips in the key show up in use. Cell 31 is written “el”, but all three times it occurs it must mean zu, which is cell 3. Cell 268 is written “em” and must be ein. In R5018 the copyist uses one sign for D and N, and one sign for Z and G; the numbered letters around each sign decide which is meant.

05 What remains uncertain

No. 1, passage N: cell 446, whose key entry was read as “Bischoff”, does not fit. The sense of the passage (measures and an accession obstructed by Spain) is C.
No. 1, passage X: cell 638 is uncertain (“Kommen” or “Kammern” in the key). Reading C.
No. 1, H: “Daroqui” as Count Tarouca, the Portuguese envoy, is M. The syllables are certain, and the next passage names Portugal.
No. 2, first passage: the cipher opens with a V-sign, giving “und Orleans”. The subject, Spain, is inferred from the context. M.
No. 3, “ein Proposition” and “die Heyrath” each contain a copyist’s wrong letter; the words are H.
All other passages are H. Letters 4, 5 and 7 of the register (book pp. 409–414, 417 onward) are not on DECODE and were not seen. The clear text of Nos. 2, 3 and 6 is summarised here, not edited.

06 Sources

DECODE (de-crypt.org): R5017 and R5018 (keys); R5019, R5020, R5021, R5022, R5023, R5024 (letters). Originals: Státní oblastní archiv v Plzni, pracoviště Klášter u Nepomuka, RA Windischgrätzů, inv. 694 karton 5, inv. 5 book 5, keys karton 164 inv. 1403 sign. 103.
Jakub Mírka, “Raně novověká šifrovaná korespondence ve fondech šlechtických rodinných archivů Státního oblastního archivu v Plzni”, Západočeské archivy 2012, pp. 44–72, reprinted in Crypto-World 3–4/2013. He describes the change of key and the two keys (n. 40–41) but gives no plaintext.

Transcriptions of both keys, the ciphertext and the readings are in the repository folder windischgraetz1720/.

Charles VI to Count Windischgrätz, 1720–1722