Thomas Phelippes is famous for having deciphered in 1586 a cipher which led to the destrcution of Mary, Queen of Scots. During the four years until the death of Francis Walsingham in April 1590, he managed intelligence gathering for the secretary. Phelippes is known to have deciphered so many Spanish ciphers that he had to keep records of known ciphers. (Oxford DNB)

The present author found Spanish letters marked as deciphered by Phelippes (Phelippes' signature can be seen in, e.g., SP53/18) in BnF fr.3641 (online catalgue, another format), which is a file of intercepted letters. They belong to two periods: December 1588 to May 1590 and October 1592 to July 1593. Since letters bearing the name of Phelippes belong to the first period, it remains to be examined by handwriting whether Phelippes was also involved in the deciphering during the latter period, which corresponds to the years 1592-1595, during which his deciphering activities are known to have been "sporadic" (Oxford DNB).

The following provides materials to aid further examination of this file.

Some of the ciphers used in these letters are Cg.13, Cp.30, Cp.34, Cp.37 as designated in Devos (1950) but others are not printed therein. See another article for more about Spanish ciphers during the reign of Philip II.

This will be referred to as "the 1589 blocked-square numerical cipher" herein for convenience. It is used in no.1 and many others among Philip II, Duke of Parma, Bernardino de Mendoza, don Juan de Idiaques. The reconstructed cipher is on f.31. There are instances assigning figure "28" to "t" rather than "u" (f.1r, line 4 and f.1v, line 1) but the above follows the table on f.31, which is consistent with the known table of Cp.37 (see another article). Use of this cipher in April 1589 is also found in BnF fr. 3977, ff.125-131 (marked "decifrada Phelippes").

This will be referred to as "the 1592 syllabic numerical cipher" herein for convenience. It is used in no.34 and many others among Philip II, Duque de Parma, Duque de Feria, Duque de Sessa, Conde de Acuna, Conde de Olivares, Conde de Fuentes de Castilla, Juan Baptista [Bautista] de Tassis, Don Diego de Ibarra, Andrea Doria.

(This turned out to be the cipher no.54 of the Nevers collection, to which my reconstruction above supplements some symbols.)

Used in no.47. This will be referred to as "the 1592 Doria cipher" herein for convenience.

Used in no.54. This will be referred to as "the 1593 Zuñiga cipher" herein for convenience.

The following ciphers are from BnF fr.3977.

Used in no.39. This will be referred to as "the 1589 Yssunca cipher" herein for convenience.

Used in no.47 and no.48.

A plus (+) sign above a figure indicates doubling the letter. A circumflex (^) above a figure appears to indicate a null.

Used in no.71.

Figures with a dot over the first digit are code numbers representing common words.

In the 1589 blocked-square numerical cipher. Interlined deciphering. "Decifrada Phelippes" (also a date in English "4 January 1589 stilo nuvo")

In cipher Cg.13. Interlined deciphering. "Decifred Phelippes" (also a date in English "30 December 1588")

In cipher Cg.13. Decipher in no.4 (but three-letter codes remain undeciphered).

Decipherment of no.3.

In cipher Cg.13. Decipher in no.7.

In cipher Cg.13. Decipher in no.36.

Decipherment of no.5.

In the 1589 blocked-square numerical cipher. Interlined deciphering.

In cipher Cg.13. Interlined deciphering. "Decifrada Phelippes"

In the 1589 blocked-square numerical cipher. Interlined deciphering.

In the 1589 blocked-square numerical cipher. Interlined deciphering.

In cipher Cg.13. Interlined deciphering. "Decifrada Phelippes"

In cipher Cg.13. Interlined deciphering. "Decifrada Phelippes"

In the 1589 blocked-square numerical cipher. Interlined deciphering. "Decifrada Phelippes"

Reconstructed cipher in the margin of f.31r.

In the 1589 blocked-square numerical cipher. Interlined deciphering.

In the 1589 blocked-square numerical cipher. Interlined deciphering. "Decifrada Phelippes"

Simplified substitution table in the margin in which, for example, "A" is assigned only "91", though "92" is also used for "a". On the other hand, each letter is assigned another symbol.

In cipher Cg.13. Interlined Deciphering. "Decifrada Phelippes"

Reconstructed cipher Cg.13 in the margin of f.37r. Notes in French, e.g., ". note un S. ainsy 65 pa 65. pas"

In the 1589 blocked-square numerical cipher. Interlined deciphering. "Decifrada Phelippes."

In cipher Cg.13. Interlined Deciphering. "Decifrada Phelippes"

In cipher Cg.13. Interlined Deciphering.

In cipher Cg.13. Interlined Deciphering.

In cipher Cg.13. Interlined Deciphering.

In the 1589 blocked-square numerical cipher. Interlined deciphering. (The recipient's first name is abbreviated as something like "+Ino", which is rendered "Inigo" in the BnF catalogue but the name may refer to commander Juan Moreo, because the abbreviation "Jno" is commonly used for "John", "Johannus", etc.)

No cipher.

In cipher Cg.13. Interlined Deciphering. "Decifrada Phelippes"

Decipherment of no.67. Some cipher (Cp.30) remains undeciphered.

A passage in cipher Cp.30 (undeciphered).

In cipher Cp.30. Decipher in no.29. The plaintext introduction seems to mention change of cipher. (Martin Idiaquez succeeded Juan de Idiaquez as Secretary of State in 1587 (Wikipedia).)

Decipherment of no.28.

In blocked-square numerical cipher Cp.37, which is similar to the 1589 numerical cipher. Interlined deciphering.

In blocked-square numerical cipher Cp.37. Interlined deciphering in part.

In Cipher Cp.30. Deciphered in separate sheet.

====Most of the following belongs to the period from October 1592.====

No cipher.

In the 1592 syllabic numerical cipher, which is somewhat similar to Cp.32. Deciphered in the margin.

In the 1592 syllabic numerical cipher. Interlined deciphering.

Decipherment of no.6. (Some code words remain undeciphered.)

In the 1592 syllabic numerical cipher. Interlined deciphering. Deciphered in the margin.

In the 1592 syllabic numerical cipher. Interlined deciphering. Deciphered in the margin.

In the 1592 syllabic numerical cipher. Interlined deciphering. Deciphered in the margin.

In the 1592 syllabic numerical cipher. Interlined deciphering.

In the 1592 syllabic numerical cipher. Interlined deciphering.

In the 1592 syllabic numerical cipher. Interlined decipherinrg.

Extract in no.66.

In cipher Cp.34. Decipher in no.44.

Copy of no.43 with interlined deciphering.

In cipher Cp.34. Interlined deciphering.

Copy of no.45 but in the 1592 syllabic numerical cipher. Interlined deciphering in the beginning. (An example of the same document enciphered in two different ciphers.)

In the 1592 Doria cipher. Interlined deciphering.

In the 1592 syllabic numerical cipher. Not deciphered. BnF fr.3982 f.175v seems to be its plaintext.

In the 1592 syllabic numerical cipher. Interlined deciphering in part (possibly because of the same content as above).

In the 1592 syllabic numerical cipher. Not deciphered (possibly because of the same content as above).

In the 1592 syllabic numerical cipher. Interlined deciphering.

In the 1592 syllabic numerical cipher. Interlined deciphering. Deciphering also in no.63.

In the 1592 syllabic numerical cipher. Interlined deciphering. Deciphered also in no.64.

In the 1593 Zuñiga cipher, basically a simple substitution cipher.

No cipher.

No cipher.

No cipher.

In the 1592 syllabic numerical cipher. Not deciphered.

In the 1592 syllabic numerical cipher. Interlined deciphering. In Italian

In the 1592 syllabic numerical cipher. Deciphered in the margin.

In the 1592 syllabic numerical cipher. Interlined deciphering.

In the 1592 syllabic numerical cipher. Interlined deciphering. Deciphered in the margin.

Decipherment of no.52.

Decipherment of no.53.

Decipherment.

Extract of no.42.f.141. Interlined deciphering. Marginal reading.

Deciphered in no.26 (f.57).

In cipher Cg.13. Interlined deciphering. In French. "Decifred Phelippes"

In cipher Cg.13. Interlined deciphering. "Decifred Phelippes"

Copy of no.51.

In cipher Cg.13. Interlined deciphering. In French. "Decifred Phelippes"

No cipher.

No cipher.

No cipher.

Cg.13. "Decifred Phelippes"

Cg.13 "Decifred Phelippes" with a date in English.

Cg.13 "Decifred Phelippes" with a date in English.

The Yssunca cipher of 1589. "Decifred Phelippes"

The 1589 blocked-square numerical cipher. "Deicifradas Phelippes"

The cipher of the Catholic League (1589). The BnF catalogue describes the letter as "contenant des nouvelles du duc de Mayenne, adressée è Claude Maumarché,... pour le Sr Pierre Letelier." "Decifred Phelippes"

The cipher of the Catholic League as in no.47. The BnF catalogue describes the letter as "d'un ligueur a un partisan du roi, qu'il s'efforce de gagner a la cause de l'Union" "Decifred Phelippes"

In Mendoza-Moreo cipher (1589). "Decifrada Phelippes"

In Vieuville-Nevers cipher (1589). This is a letter from the Marquis of Vieuville (Wikipedia) to the Duke of Nevers (Wikipedia). A specimen is given in another article.

The following is from no.14 (the 1589 numerical cipher) marked "Decifrada Phelippes."

The following is from no.8 (the 1589 numerical cipher), not bearing the name of Phelippes.

The following is from no.38 (the 1592 syllabic cipher), not bearing the name of Phelippes.

©2017 S.Tomokiyo

First posted on 15 April 2017. Last modified on 29 December 2017.

Cryptiana: Articles on Historical Cryptography