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Esztergom → Ferrara · Italian chancery letters · 1493 · not a cipher

Three clear letters among Costabili's cipher records

Ercole I d'Este
toErcole I d'Este

Three letters from Beltrame Costabili to Ercole d'Este contain ordinary Italian writing and belong outside the open cipher list.

Daniel Bourdeau · posted · updated

Method: not a cipher

Credits · Brice Dudout (pointer to a source)

At a glanceNot applicable · no cipher passage identified

The letters
Costabili's reports to Ercole I d'Este, dated 13 March, 22 April and 18 July 1493.
Where
Archivio di Stato di Modena, Ambasciatori Ungheria b. 2/22 nos. 5, 6 and 9; DECODE R1095–R1097.
The finding
The bodies and their address leaves are clear chancery writing. The contractions are ordinary abbreviations.
How checked
Both full photographs on each record were inspected. No substituted alphabet or numerical cipher run was found.
Still open
The separate Costabili letters of 1491–92 remain in catalogue item 361.

01 The three records

DECODE labels these letters Partially decrypted. Catalogue item 361 consequently included them in a group of ten Costabili records requiring investigation. Their six photographs show three clear letters and three address or docket leaves.

RecordDateModena shelfmarkPhotographs
R109513 March 1493Ambasciatori Ungheria b. 2/22 no. 5I5642–I5643
R109622 April 1493Ambasciatori Ungheria b. 2/22 no. 6I5644–I5645
R109718 July 1493Ambasciatori Ungheria b. 2/22 no. 9I5646–I5647

02 What the inspection establishes

The bodies run continuously in Italian, using familiar chancery contractions for titles, forms of address and common words. They are signed by Costabili. The April letter acknowledges an earlier letter and reports the good bodily health of the duke's son. The July letter mentions the Venetian ambassador's household and Tadio de Lardi before reporting the son's health.

This is a correction to the classification of the records, not a cryptanalytic solution. No new key, complete diplomatic transcription or new interpretation of the correspondence is claimed. A proposed DECODE correction has been queued; it has not been sent.

03 What remains open

The earlier cipher letters remain separate. The four photographs attached to R1163 are byte-for-byte identical to the four attached to R1164; those records therefore provide no independent duplicate text for cryptanalysis. That finding does not resolve their cipher passages.

The full photographs are available through DECODE authentication. Its source notices require the archive's permission to publish them, so no scan is reproduced here. File sizes and SHA-256 hashes are retained in the repository's evidence manifest.

04 Sources

Inspection notes and profile: targets/costabili1493.