gap que, sof de, qib el, coh Su Santidad, bas V.Md.). The key already recovered in the Sessa 1524 write-up applies unchanged.
As a check, one cipher paragraph of the uncalendared 20 February letter was decrypted with it, and about half its tokens resolve at once.
Extent: four letters are in print as English abstracts. Of the two uncalendared letters, 26 April is decrypted in full and 20 February about 57% (section 03). The rest is transcription and decryption with a known key.
01The seven records
| DECODE | Salazar A-27 | Date line | Bergenroth, CSP Spain vol. 2 |
|---|---|---|---|
| R9660 | ff. 141–147 | En Sesa a xx de hebrero de 1523 | not calendared |
| R9661 | ff. 149–152 | En Roma, miercoles iiij de março 1523 | no. 534 (calendared from the f. 190 copy, “in cipher with contemporary deciphering”) |
| R9662 | ff. 308–326 | [12 April 1523] | no. 541, “a duplicate of the preceding despatch” |
| R9663 | ff. 327–341 | [11 April 1523] | no. 540 (ff. 327–343, “contemporary deciphering”) |
| R9664 | ff. 418–422 | De Roma xxv de abril 1523 | duplicate of no. 544 (ff. 424–430 deciphered) |
| R9665 | ff. 437–438 | De Roma xxvj de abril 1523 | not calendared |
| R9666 | ff. 439–441 | April 1523 | no. 545, clear |
The Emperor’s side of the same exchange (Valladolid, 8 and 15 February 1523, answering Sessa’s letter of 17 December) is in CSP nos. 528–530. Sessa’s 20 February letter opens with that December letter: A los xvij de dizienbre escrevi a V. M.
02A sample: the 20 February letter, f. 141r
Decrypted by hand with the 1524 key. Known groups are rendered as words, spelled letters are hyphenated and unvalued groups are in brackets:
¶ muy despues [cag] a [d3]-a-do a V.Md. de la con-[…] y forma que el papa [cas] / … el p-l-l-i-g-r-o m-a-n-i-f-… en que se ponian / la cosa … al [kor] con la c-e-r-t-i-z-a que el [yim] de … estonces dava / de la [bog]-da de franceses / el [bao] se [set] de [bla] a ve-r a Su Santidad, mas con color de … de ningun-… disposicion de entender / … y si no es … a lo que V.Md. [kim] se / entre tanto avisarle.
The clear resumes: Hizose asy. Fuimos en Roma a los xxvj del pasado; entro con muy buen recibimiento, y el posar fue en palacio. The full token list is in targets/sessa1523/reading_f141_sample.txt.
03The two uncalendared letters, decrypted (21 September 2026)
R9665, 26 April: decrypted in full. The letter is in clear apart from three short runs. The first, on f. 437r, decrypts with the key as Su Santidad por esta bula es declarado contra Francia, and a note in the margin, written when the letter arrived, says the same thing word for word. The note also gives one group the 1524 key lacked: hef = por. The two runs on f. 437v were deciphered between the lines at the time: …al de Ancona (Cardinal Accolti, praised as muy buen servidor de V. Mt.) and Su Sd. mejoro ayer.
R9660, 20 February: transcribed in full, about 57% decrypted. About 2,050 cipher tokens on ff. 141r–147r, of which about 57% decrypt with the key extended by 15 values found in context: yim duque, bla ir, boz -io, loz obisp-, gam como, and the spelled V-o-l-t-e-r-a, which fixes three letter values. The letter covers Adrian VI’s irresolution towards the French and his refusal to join the league or give French envoys a safe-conduct; the viceroy Lannoy’s visit; Francis I’s plan to take a third of church revenue in France; the Swiss envoys’ pay; the Duke of Bari; Modena and Reggio against Alberto Pio, committed to Cardinals Volterra, Monte and Iacobacci; Soderini waging war on the Medici como enemigo; Siena after Petrucci’s death; the bishopric of Tortosa. Decryptions: targets/sessa1523/reading_r9660.txt, reading_r9665.txt.
04What remains
- About 150 code groups of R9660 (about 40% of its tokens; the commonest
cas,cag,min,rep) have no attestation in any decipherment on DECODE. The court’s decipherment leaves of the sister letters (ff. 190, 342–343, 424–430) would value them and are only at the RAH. - The calendared letters are in print only as English abstracts. The Spanish decipherments are on RAH leaves outside these records.
- The groups still open in the 1524 key (
vo,per,hay) are still unvalued;rucis a verb root, not a person. The sample’s word-level decryptions are grade C.
05Sources
- Real Academia de la Historia, Madrid, Colección Salazar y Castro A-27 (signatura 9/27), via DECODE R9660–R9666 (images by permission of the Academia).
- G. A. Bergenroth, Calendar of State Papers, Spain, vol. 2 (1866), nos. 528–545: March 1523, April 1523.
- The key: Sessa 1524,
targets/sessa1524/key_working.md.
Notes, profile and sample reading: targets/sessa1523/ in the repository.