Finding the Keys to Philip II's Cipher Letters to Juan de Vargas Mexia

BnF es.132 (Espagnol 132, historically also catalogued as Regius 9999 or Mazarin 498) (Gallica) contains many letters of Philip II to Juan de Vargas Mexia [Mejia], ambassador in Paris from 1577 until his death in 1581. These undeciphered despatches seemed interesting to historians (catalogs in Spanish (1844, 1847)). For example, Rubino (2012) points out that f.198 may contain new facts about the murder of Escobedo allegedly organized by Antonio Perez (Wikipedia), but the cipher letters remain undeciphered (Rubino (2012)).

Of the four ciphers used in the volume, I cracked one in August 2020 and identified the three others among the known ciphers. This will allow historians to decipher all the letters in the volume. (As for f.198, I read words such as "le Marques de los Velez", "Escovedo", "mi inocencia", "falso testimonio", etc.)

Four Ciphers used between Philip II and Juan de Vargas Mexia

Four ciphers are used in many undeciphered letters in BnF es.132. For convenience's sake, I call them Vargas Mexia's Ciphers 1-4 herein.

Vargas Mexia's Cipher 1

Used in the first letter from the king to Vargas Mexia in the volume (f.3) dated 16 December 1577. The cipher was reconstructed by Devos (1950), p.418, from Vargas Mexia's letter of 12 December 1577. I realized it a few days after I posted the present article. (At first, I thought use of diacritics was not consistent with this cipher, and gave up the idea when the first few words did not make sense.) The substitution below has been supplemented with information kindly provided by Demetrio Martín Vilela from Argentina.

The substitution table above does not include some symbols in Devos (1950) that could not be confirmed in my specimen. In particular, Devos assigns 12 for "a", 21 for "e", and 31 for "u". Devos records code elements with figures with a plus sign above (61 for "paz", 85 for "qual", 93 for "rey") and monosyllables (bis for "reyno", nos for "Vra. Magd.", to for "hermanos").

Vargas Mexia's Cipher 2

Used at least from January to March 1578. I cracked this in August 2020. This is the simplest of the four, and possibly for that reason, it was short-lived.

Vargas Mexia's Cipher 3

Used at least from March 1578 to May 1580. This was also used by Bernardino de Mendoza, ambassador in England, and Don Juan de Borgia, ambassador at the imperial court then at Prague. The original cipher is printed as Cp.30 in Devos (1950). I independently reconstructed this as "Cipher with Don Juan de Borgia", so did Bernard Allaire and Devos himself (see another article).

Vargas Mexia's Cipher 4

Used at least from September 1578 to April 1579. This was also used in letters of Antonio Perez. This was reconstructed by Devos (1950), p.422, from Vargas Mexia's letter of 16 May 1579.

In the substitution alphabet above, "a" and "v" (cursive) representing "u" and "o", respectivey, are my additions. Double consonants "fl", "gl", "pl", "br", "cr" are my conjectures by analogy from Cg.8 (some of which I confirmed by actual examples). Devos (1950) notes two letter symbols: "vo" for "V^ra. Magd." and "o" for "hu", to which I may add "co" for "carta" (f.123).

According to Devos' reconstruction, a haček (ˇ) is a null, and a plus sign (+) or a caret (^) over a character doubles the letter. In the ciphertexts I examined, a caret (^) seems to be used to indicate a null.

This cipher is similar to Cg.8 (1572) in that two-letter syllables are represented by a base symbol (arabic numeral) and a vowel indicator and that the base symbol is the same as in the cipher alphabet. Further, three-letter symbols are formed by combining a plaintext letter with a vowel indicator. That is, symbols for bla, cla are formed by combining capital letters B, C with a vowel indicator, while symbols for gra, fra, pra, tra are formed by combining small letters g, f, p, t and a vowel indicator.

Codebreaking of Philip II's Cipher (1578) with Vowel Indicators

Vargas Mexia's Cipher 2 above was cracked by myself on 1 August 2020. This section reports how I solved this cipher.

As already discussed in another article, once one knows the vowel indicator system typical of the Spanish ciphers at the time, the system facilitates codebreaking by revealing which symbols are vowels and which are consonants. Moreover, occasionally, word divisions are apparent in the ciphertext in this volume. To my luck, as it turned out, the cipher is one of the simplest of the kind.

Of the many undeciphered letters in BnF es.132, the letter of Philip II to Juan de Vargas Mexia, dated 24 January 1578, seemed a good starting point because of its clear handwriting and preservation of word divisions. I was sure this four-page letter would be more than sufficient to solve this cipher.

Weakness of the Vowel Indicator System

The so-called vowel indicator system uses diacritic signs to indicate vowels following consonants represented by base symbols. For example, in Cp.30 (which had been known to me before I realized it was the same as Vargas Mexia's Cipher 3 above), "15" represents "l", while "15+" represents "la", "15." represents "le", etc.

When one knows such an enciphering scheme, symbols that occur with diacritics can be known to be consonants. When there occurs "11^ 18 11." (for my transcription convention, see below), "18" is likely to be a consonant. (There are exceptions. In this case, I was almost sure at once that "6", seldom accompanied by a diacritic sign, would be a vowel, but the few examples of "6" with a diacritic sign kept me from making this conclusion for some time. At one time, I thought "6" might be "u/v", but it seemed too frequent. I am still unsure of the reading of "6 with diacritics" as in "los lieos" and "so ee". The latter occurs multiple times, and does not seem to be an enciphering error.)

Pattern Matching

When word divisions are apparent, we may immediately determine some words by pattern matching. For example, the word "6 13 p+ 19+ 13+ 17" (first line on f.11v) gives a match "e n ve ne ne s", though this was not convincing because both 19 and 13 correspond to "n". Then, it occurred to me that "p+" might represent a double-consonant syllable (e.g., "bla", "cra", etc.) as in another cipher used by Vargas Mexia at about the same time (printed in Devos (1950) p.422), which later turned out to be Vargas Mexia's Cipher 4 above. If so, the above pattern gives a match "e n tre te ne d/n/s/r." This seemed plausible. The pattern "pe 19e 5^ 18" on the next line gave "tra ta do s." (Even without frequency counting, the high frequency of 18 was obvious, and I thought it to be either N or S or R.)

Counterevidence

Although these turned out to be correct in the end, I was not yet sure. For one thing, the above identifications do not match "6 18 f. 20. 18," for which I thought "esclavas" was the most likely in my dictionary. (I gave up the conjecture 6=u (see above) because there was no matching pattern for 6=u. Since 6 often occurs at the beginning of a word, I thought 6 was either "a" or "e". Since "18" occurs before a double-consonant syllable, it should be either "n", "m", or "s".) This requires "." rather than "e" (diacritics; for my transcription convention, see below) to be "a", which does not match the above (correct) identifications. (The final key gives "escrivis", of which my dictionary gave the spelling "ESCRIBIS".)

Another concern was: "2 5 20+ 17 19 17 12+" on the same page gave "investiste", but assigning both 19 and 12 to "t" did not seem right. (As it turned out, "12+" is not part of the word. I was aware "2 5" may not be a part of the word, but "12+" looked closely following the preceding symbol that I didn't think it separate.)

Breakthrough

I decided some statistical analysis was necessary, and began transcribing the ciphertext. In the process, I noticed that numbers occurring in the ciphertext were limited to 1-22. This suggested a possibility of simple monoalphabetic substitution (aside from the vowel indicators). Moreover, I was aware that "2" occasionally occurs on its own, and I thought it might be a one-letter word "a".

Now, I already had a tentative assignment 6=e. Can this be a straightforward assignment 2=a, 3=b, 4=c, 5=d, 6=e, ...? (Such too-good-to-be-true cases often happen in historical ciphers. I experienced similar luck in solving Schiner's Cipher and Ormonde-Clanricarde Cipher. Leighton and Eric Sams and Julian Moore wrote about similar cases.) The other assignments 13=n, 19=t, and 17=d/n/s/r match this hypothesis. When I applied this to read the ciphertext, I soon realized this was correct.

Determination of Vowels

In order to determine the vowels, I counted diacritics occurring in my transcription of first one or two pages. The result was as follows. (This was all the statistics I used in this cryptanalysis.)

When I applied the vowels in descending order in Spanish (E-A-O-I-U), E, A, and I seemed right. It took some time for me to decide which of the remaining diacritics (^ and .) represent "O" and "I", but when I read "mi hermano", I had no further qualms in my identifications.

Some Interesting Patterns

Of some interesting patterns I found when trying pattern matching, "12e 5e 12e 12. 9+ 17 12e" turned out to be "madama mi hermana" (madame, my sister); "6 13 13^ 16+ 17+ 17 11+" turned out to be "en no quererle" ("in not loving him" according to machine translation).

Partial Transcription of Ciphertext

Just for record, the following is my partial transcription of the ciphertext. (I only used this for counting diacritics.) My transcription uses the following convention for diacritics.

11^ 18 11. 6^ 18 6+ 12+ 6 18 f. 20. 18 16+ 12^ 18 5+ 3e 20 18 14 18 9e 20. **
12^ 18 pe 5^ 16+ 11+ 6 12 3. 14 12. 9+ 17 12e 13^ 15e 17e 16+ 10 12 n. 12. 6 18+ 17 2~
9^ 11 8e 17. 2 5+ 20+ 17 11^ 18 2 13 19+ 18 16+ 6 18 19^ 18+ 9. ♀. 6 18+ g 2 18. 18+
17e 3. 6 13 16+ n^ 4. 17+ g 18 5+ 9e 20+ 17 11^ 18 4^ 13 5. 18. 12. 11e 3. 14 13 ρ 6 12 3.
2 17 14 11^ 18
(f.11v)
11^ 16+ 12+ 6 18 f. 20. 18 18^ 6+ 6 11 6 13 p+ 19+ 13+ 17 11e 18 me 19. 3e 18 5**
11^ 18 pe 19e 5^ 18^ 2 13 20. 11e ρ 19+ 13+ 17 11e 18 3^ 13 11e 3e 18e 5+ 8・ ρ **
me haparecido demucha configeracion ...
yassi lo sera queros por V'ra parte 18. 13 16+ 6 11 20 13^ 18+ 15e 5+ 11 1**
p^ 3^ 12^ 2 5 20+ 17 19. 18 vais haziendo ...
officios queos pareciere 3^ 13 11^ 18 5+ 11+ 20 13e 3e 18e ρ 5+ 11e 14 pe d**
..
9e 20+ ρ 18 9+ c^ 12.ρ 3. 6 13 5+ 2 5 20+ 17 19 17 12+ 5+ 11^ 16+ 9e 20+ ρ 18 **
19+ 13 5. 5e~ 5^ 5+ 11^ 18 〓 11+ 18 16+ 18+ 2 17 12e 20e 13 6 13 11e 18 3^ 1**
19e 18 5+ 8. ρ 6 13e ρ 13^ 17 12e 13 5. 2 15e 17e ρ 17 2 11e 18 10 13 5. 2 18 **
19e 12 3. 6 13 6 11 5+ 18 14 16+ 19. 6 13+ 6 11 5+ 3+ 2 17 13+ 5+ 15^ 13+ 17 15.
6 13 11^ 5+ 13e 20+ Re y delo que mas entendieredes ...

16+ 5^ 2 20. 18e 5^ 5+ 11^ 16+ 12+ 6 18 f. 20. 18 5+ 11e 15^ 4e 18e 19. 18 7e 3. 14 13
16+ 11e R+ρ 13e 12e 5 17+ 19. 6 13+ 5+ 11 5・ 16+ 5+ g^ 17+ 13 4. 2 ρ 11e 4e
18e 5+ v^ ρ 4. 6 17 19^ 6 18 5+ 12e 18. 2 5^ 6 11 4・ ρ 5e 5^ 16+ 19 6 13+ 6 11 **
16+ 6 13+ 18 19e 18 4^ 18e 18 5+ 10 13 19+ 17+ 18 15^ 17 16+ 3e 18. 11^ 12. 18 12^ 1**
ge ♀+ 4^ 13 11e R+ ρ 13e 12e 5 17+ 9e 9+ c^ 4^ 13 12e 5e 12e 12. 9+ 17 12e
6 13 13^ 16+ 17+ 17 11+ 2 4・ 5. 17 4^ 13 11e R+ 13 19e ρ 9e ♀. 6 13 5e 16+ 6 13 2 16+
6 18 19e 5^ 19 6 13+ 4^ 12^ 18・ 15e 5 17+ 11+ {19+ 13 2} 24・ 5. 2 ρ 2 20 13 16+ ρ 9**
6 12 3. 2. 5^ 15+ 17 18^ 13e n^ 15. 2 2 15+ 5. 17 11+ 15+ 18+ 4^ 12 15^ 13 8e 6 18 19+
13+ 8^ 4. 14 15^ 17 3. 6 13 13e~ 13^ 9e 16+ 17. 5e~ 5^ 9e ♀. 17 4^ 18e 13. 13 8・ 13e
ρ 13^ 18+ 17. 2 12e 11^ 16+ 20^ 18 2 ve 4^ 13 6 18 19e 14 4e 18. 14 13 n^ 4・ 17+ 5+

(f.12)
4^ 12^ 5+ 20. 6 18 ρ 4^ 13 Pe 13 5. 18. 12・ 11e 4. 14 13 ρ 12e 13e~ ve
16+ 11e 15^ 4e 18e 19. 18 7e 4. 14 13 16+ 11e R+ ρ 13e 19. 6 13+ 5+ 11 5. c^
5・ 16+ 18+ 4^ 13 16. 13・ 2 18+ ρ 16+ 18+ 20. 13. 6 18+ 13 2 2 Pe 20+ 18e 17
4^ 13+ 18 19e 14 4e 18. 14 13 15^ 17 16+ 2 18. 15^ 5 17. 2 2~ 18+ 17 16+ 2 11 8・ 13
5. 2 13^ 18 10・ 13 19e 18+ 12^ 18^ 15e 17e 13^ 15+ 17 12. 19. 22 16+ 6 11 5. 16+ 18e 11
8e 4^ 13 16. 2 13 19e 18 4^ 18e 18 5+ 18 16e 4e 11+~ 11. 5e 5 18+ 14 f~ h+ 4+ 13

Use of Duplicates

Important dispatches were often sent in duplicates. The following image shows that (in this case) duplicates were independently enciphered (rather than a copyist making a duplicate of an enciphered letter). The duke of "Alençon" is enciphered as "Alancon" in one and "Alanson" in the other. This small specimen includes at least one (and probably more) errors in enciphering (see "[r]ey", "rre rre").

Where one uses a code word and the other uses syllabic symbols, the two may not look like the same text.

F.165 is a duplicate of f.167, and also enciphers the introductory part left in the clear in the latter. The original f.167 has a text in the margin, which is to be inserted at a potision indicated by a T-like sign. The duplicate f.165 incorporates this additional text in the body. As with the above, these are independently enciphered (for example, "personas particulares" are enciphered with code symbols in f.165 but with syllables in f.167.)

The introductory paragraph of f.171 includes a passage that is not included in the duplicate at f.174. It reads something like: "de que Va con esta el dup^da el qual sera bien quele embiecis abuen recaudo y queme aviseis decomo lo ha ureis hecho / yeneaso queno huviese llegado elprimer despacho le despachareis correo endiliy encia coneste." (I have seen other specimens in which a passage mentioning a duplicate is not present in the duplicate.)

Table of Contents for BnF es.132

•no.1 (f.1) Philip II to "al marques de Ayamonte," D. Antonio de Guzman y Zuniga, Governor of Milan. S. Lorenzo, 19 October 1577
•no.2 (f.3) Philip II to Juan de Vargas Mexia. Madrid, 16 December 1577. (Vargas Mexia's Cipher 1) undersigned by Cayas (My preliminary decipherment of this letter is presented in "Reading an Undeciphered Letter of Philip II to Juan de Vargas Mexia (1577)" (Academia.edu).)
•no.3, 4 (f.5, 6) Philip II to Juan de Vargas Mexia. Madrid, 18 December 1577 and 16 January 1578
•no.5 (f.7) Philip II to Juan de Vargas Mexia. Madrid, 18 January 1578
•no.6 (f.9) Philip II to Juan de Vargas Mexia.
•no.7 (f.11) Philip II to Juan de Vargas Mexia. Madrid, 24 January 1578 (Vargas Mexia's Cipher 2) undersigned by Antonio Perez
•no.8 (f.14) Philip II to Juan de Vargas Mexia. S. Lorenzo, 31 January 1578
•no.9 (f.15) Philip II to Juan de Vargas Mexia. Madrid, 19 February 1578
•no.10-16 Philip II to Juan de Vargas Mexia. Madrid, 8 and 16 March, et S. Lorenzo, 16 et 17 mars 1578.
no.10 (f.17) 8 March 1578 (Vargas Mexia's Cipher 2) undersigned by Antonio Perez
no.11 (f.22; duplicate of no.10) (Vargas Mexia's Cipher 2) undersigned by Antonio Perez
no.12 (f.26) (Vargas Mexia's Cipher 2)
no.13 (duplicate of no.12)
(f.27-31 are missing in pdf)
no.15? (f.32) 17 March 1578 (Vargas Mexia's Cipher 3) undersigned by Cayas
no.16? (f.34) 16 March 1578 (Vargas Mexia's Cipher 2) undersigned by Antonio Perez
•no.17 (f.36) Philip II to Juan de Vargas Mexia. Madrid, 12? April 1578
•no.18-19 (f.37, 39) Philip II Juan de Vargas Mexia. Madrid, 15-16 April 1578 (Vargas Mexia's Cipher 3) undersigned by Cayas
•no.20 (f.40) Philip II to Juan de Vargas Mexia. Madrid, 17 April 1578
•no.21-23 (f.41, 44, 46) Philip II to Juan de Vargas Mexia. Madrid, 29 April 1578 (Vargas Mexia's Cipher 3) undersigned by Antonio Perez
•no.24 (f.48) "Hernando de Escobar" to Juan de Vargas Mexia. Madrid, 31 May 1578
•no.25-29 (f.50, 54, 58, 60, 62) Philip II to Juan de Vargas Mexia. Bosque de Segovia, 7 and 14 June 1578 (Vargas Mexia's Cipher 3)
•no.30 (f.66) "Ant[onio] Perez" to Juan de Vargas Mexia. Segovia, 15 June 1578
•no.31 (f.68) "Hernando de Escobar" to Juan de Vargas Mexia. 18 June 1578
•no.32 (f.70) "Caterine" de Medicis to Juan de Vargas Mexia. Chantilly, 9 June 1578 (French)
•no.33-35 (no.35 is a duplicate of no.34) (f.71, 73, 75) Philip II to Juan de Vargas Mexia. Madrid, 19 and 31 July 1578 (Vargas Mexia's Cipher 3)
•no.36 (f.77) Philip II to "Alonso de Curiel." Madrid, 31 July 1578.
•no.37-40 (no.39 is a duplicate of no.38) (f.79, 81, 83, 85) Philip II to Juan de Vargas Mexia. El Pardo, 4 August; Madrid, 18 August and 10 September 1578 (Vargas Mexia's Cipher 3)
•no.41 (f.87) "Ant[onio] Perez" to Juan de Vargas Mexia. Madrid, 13 September 1578 (Vargas Mexia's Cipher 4)
•no.42-43 (no.42 is a duplicate of no.43) (f.89, 93) Philip II to Juan de Vargas Mexia. Madrid, 19 September 1578 (Vargas Mexia's Cipher 3)
•no.44 (f.97) "arcivescovo di Nazarett," Fabio Miro Frangipani, to Philippe II. Paris, 25 September 1578 (Italian)
•no.45 (f.99) Philip II to Juan de Vargas Mexia. Madrid, 13 October 1578
•no.46 (f.101) (duplicate) Philip II to Juan de Vargas Mexia. Madrid, 13 October 1578
•no.47-48 (no.47 seems to be a duplicate of no.52) (f.103, 105) Philip II to Juan de Vargas Mexia. Madrid, 13 October 1578 (Vargas Mexia's Cipher 3)
•no.49 (f.107) Philip II to M. "de la Mote, gouverneur et capitaine... de Gravelinghes." 13 October 1578 (French)
•no.50 (f.109) Philip II to "Alonso de Curiel." 13 October 1578
•no.51 (f.111) Philip II to "M. de la Mota." 13 October 1578
•no.52 (see no.47) (f.113) Philip II to Juan de Vargas Mexia. 13 October 1578 (Vargas Mexia's Cipher 3)
•no.53 (f.115) Philip II to Juan de Vargas Mexia, Madrid, 14 October 1578
•no.54 (f.117) (duplicate) Philip II to Juan de Vargas Mexia. Madrid, 14 October 1578
•no.55 (f.119) Philip II to Juan de Vargas Mexia. Madrid, 15 October 1578 (Vargas Mexia's Cipher 3)
•no.56 (f.121) Philip II to "duque de Sessa." S. Lorenco, 19 October 1577
•no.57 (f.123) Philip II to Juan de Vargas Mexia. Madrid, 20 October 1578 (Vargas Mexia's Cipher 4)
•no.58 (f.125) Philip II to Juan de Vargas Mexia. Madrid, 21 October 1578
•no.59 (f.127) Philip II to Juan de Vargas Mexia. Madrid, 26 October 1578
•no.60-62 (no.61 is a duplicate of no.60) (f.129, 132, 134) Philip II to Juan de Vargas Mexia. Madrid, 1 and 2 November 1578 (Vargas Mexia's Cipher 3)
•no.63 (f.136) "Ant[onio] Perez" to Juan de Vargas Mexia. Madrid, 5 November 1578
•no.64-68 (no.65 is a duplicate of no.64; no.67 is a duplicate of no.66) (f.138, 140, 142, 144, 146) Philip II to Juan de Vargas Mexia. Madrid, 12 and 20 November 1578 (Vargas Mexia's Cipher 3)
•no.69 (f.148) "Ant[onio] Perez" to Juan de Vargas Mexia. Madrid, 21 November 1578
•no.70 (f.150) Philip II to Juan de Vargas Mexia. Madrid, 30 November 1578 (Vargas Mexia's Cipher 3)
•no.71 (f.152) Philip II to Juan de Vargas Mexia. Madrid, 30 November 1578
•no.72 (f.154) Philip II to Juan de Vargas Mexia. El Pardo, 4 December 1578 (Vargas Mexia's Cipher 4)
•no.73 (f.157) "Ant[onio] Perez" to Juan de Vargas Mexia. Madrid, 8 December 1578 (Vargas Mexia's Cipher 4)
•no.74 (f.161) Philip II to Juan de Vargas Mexia. El Pardo, 12 December 1578 (Vargas Mexia's Cipher 3)
•no.75 (f.163) Philip II to Juan de Vargas Mexia. El Pardo, 18 December 1578
•no.76-77 (no.76 is a duplicate of no.77) (f.165, 167) Philip II to Juan de Vargas Mexia. S. Lorenco, 10 January 1579 (Vargas Mexia's Cipher 3)
•no.78 (f.169) Philip II to Juan de Vargas Mexia. (decipherment) El Pardo, 22 January 1579
•no.79-80 (no.80 is a duplicate of no.79)(f.171, 174) Philip II to Juan de Vargas Mexia. El Pardo, 23 January 1579 (Vargas Mexia's Cipher 3)
•no.81 (f.177) Prince de Parme, Alexandre Farnese, to Juan de Vargas Mexia. (decipherment) 25 January 1579
•no.82 (f.179) "Ant[onio] Perez" to Juan de Vargas Mexia. Madrid, 26 January 1579 (Vargas Mexia's Cipher 4)
•no.83 (f.181) Philip II to Juan de Vargas Mexia. El Pardo, 7 February 1579 (Vargas Mexia's Cipher 3)
•no.84 (f.183) "Leonor de Montmorency," comtesse de Hooghstraeten, to Philip II
•no.85 (f.185) Philip II to Juan de Vargas Mexia. Madrid, 18 March 1579 (Vargas Mexia's Cipher 3)
•no.86 (f.191) Philip II to Eleonore de Montmorency, "condesa de Ocstrata" (Hooghstraeten)
•no.87 (f.193) Philip II to "Pedro de Arcauti". 18 March 1579
•no.88 (f.195) Philip II to Juan de Vargas Mexia. Madrid. 18 March 1579 (Vargas Mexia's Cipher 3)
•no.89 (f.198) "Ant[onio] Perez" to Juan de Vargas Mexia. Madrid, 15 April 1579 (Vargas Mexia's Cipher 4)
•no.90-91 (f.200, 202) Philip II to Juan de Vargas Mexia. S. Lorenco, 21 April, and Aranxuez, 17 May 1579 (Vargas Mexia's Cipher 3)
•no.92 (f.204) "Francoys" de Valois, duc d'Alencon, to "Messieurs Estatz generaulx des Pays-Bas." Paris, 13 June 1579. (French)
•no.93-97 (f.206, 208, 211, 213, 215) Philip II to Juan de Vargas Mexia. Tolede, 8 June; Aceca, 4 June; S. Lorenco, 3 July, 7 July; El Pardo, 13 July 1579 (Vargas Mexia's Cipher 3)
•no.98 (f.217) Philip II to M. "de Lansac". S. Lorenco, 22 August 1579
•no.99-105 (f.218, f.220, f.222, f.224, f.226, f.228, f.231) (no.102 no.103, and no.105 are duplicates of no.100, no.101, and no.104) Philip II to Juan de Vargas Mexia. S. Lorenco, 24 August, 13 September, 13 October 1579 (Vargas Mexia's Cipher 3)
•no.106 (f.233) "Alessandro Farnese," prince de Parme, to Juan de Vargas Mexia. Mastricht, 1er November 1579 (Vargas Mexia's Cipher 3)
•no.107-110 (f.235, f.237, f.239, f.241) (no.108 and no.110 are duplicates of no.107 and no.109) Philip II to Juan de Vargas Mexia. El Pardo, 3 November, 13 November 1579 (Vargas Mexia's Cipher 3)
•no.111 (f.243) "El conde [Pedro-Ernesto] de Mansfelt" to Juan de Vargas Mexia. Valenciennes, 19 November 1579
•no.112 (f.245) Philip II to Juan de Vargas Mexia. El Pardo, 29 November 1579 (Vargas Mexia's Cipher 3)
•no.113 (f.247) (duplicate of no.112) Philip II to Juan de Vargas Mexia. El Pardo, 29 November 1579 (Vargas Mexia's Cipher 3)
•no.114 (f.249) "Don Juan de Acuna" to Juan de Vargas Mexia. Mastricht, 8 December 1579
•no.115-123 (f.251, f.253, f.255, f.257, f.261, f.263, f.267, f.269, f.271) (no.119 is a duplicate of no.117; no.118 is a duplicate of no.120) Philip II to Juan de Vargas Mexia. Madrid, 16 January; Guadalupe, 28 March; Merida, 16 May 1580 (Vargas Mexia's Cipher 3)
•no.124 (f.273) Philip II to Juan de Vargas Mexia (Vargas Mexia's Cipher 2)
•no.125 (f.275) Philip II to Juan de Vargas Mexia (Vargas Mexia's Cipher 3)
•no.126 (f.277) "Dichiaratione di Monsigre il duca [Francesco] d'Alonsa (Alençon) sopra la sua partita de la corte di Francia." Dreux, 17 September 1575 (Italian)
•no.127 (f.279) "Relacion del movimiento de Franceses a la parte de Fuenterravia. Para embiar a Juan de Vargas." August 1579
•no.128 (f.281) Memoire (French)
•no.129 (f.283) "Articles concernans la police...." (French)
•(f.287) "Au lecteur salut" (French)

References

Devos, J. P. (1950), Les chiffres de Philippe II (1555-1598) et du Despacho universal durant le XVII^e siècle

Samantha R. Rubino (2012), "The Secrets of Antonio Pérez Decoded" (The Ohio State University. Department of History Honors Theses) (OSU)

S. Tomokiyo, "Reading an Undeciphered Letter of Philip II to Juan de Vargas Mexia (1577)" (Academia.edu)