Regular Cipher Mysteries readers will know that I’m pretty good at digging historical things up, at shining lights under long-unmoved archival rocks. Well… my challenge this week was to find some mid-Quattrocento Milanese enciphered letters, and though I’ve possibly got most of the way to an answer, I’ve ended up a bit stuck, and would really appreciate some help from all you good people!
The starting point was that I was sure that the Archivio di Stato in Milan contains a vast number of documents from the period I’m most interested in (Milan’s Francesco Sforza era, i.e. 1450-1465), so that ought to be the first place to look for these. But (as is normally the case) relevant manuscript catalogues are few and far between online, so I initially drew a blank.
Then I (somewhat luckily) stumbled across a 1995 book online called “Fifteenth-century Dance and Music: Treatises and Music” by A. William Smith. Page 6 of its “Fifteenth-century Italian Dance Sources” chapter mentions a letter: “26 July Archivio di Stato milanese. Potenze estere. Napoli 1455. in cifre from Albrico Maletta, Sforza ambassador in Napoli to Duke Francesco Sforza in Milano.” Interestingly, f20v of the famous Tranchedino cipher ledger is marked as “Cum Francisco Maleta” (though this is sandwiched between a 1458 cipher and a 1459 cipher, so might well have been entered into the ledger later than 1455): all the same, it would be interesting to compare the two. But how to find the manuscript reference for this?
The first thing to note is that “Potenze Estere” is actually the name of a large set of documents within the Milanese Carteggio Sforzesco archive. Obviously, I then searched like crazy for (I’d guess a scan of a 19th century) inventory of this, but without any luck. So where next?
Then I remembered Aloysius Meister’s “Die Anfaege Der Modernen Diplomatischen Geheimschrift” (1902): p.30 contains a (surprisingly complex, I think) Milanese cipher key and nomenclator dated 14th March 1448, with the reference “Mailand, Staatsarchiv. Pot. Est. Cifre Fasc. 2 Nr 5.” There’s also a 1483 cipher (p.31) noted as “l. c. Fasc. 1 Nr 15” (interestingly, this contains a “4o” composite character (for ‘z’) but with the ‘o’ attached to the downstroke of the ‘4’), and a 1530 cipher key (p.32) listed as “l. c. Fasc. 4 Nr. 53 Grofs 4o”.
(I should add that Meister 1902 also lists ciphers for Modena, including one [p.35] dated 23rd June 1435 “In Milano” which fascinatingly contains “4” for ‘Q’ and “4o” for “Qua”. [“Canc. duc. Arch. Proprio Mappe II. Nr 1.”]: and for Florence, he lists the Cifra di Galiotto Fibindacci da Ricasoli 1424, which similarly uses “4o” for “Q” [p.50])
So there you have it: it seems that the Carteggio Sforzesco’s Potenze Estere archive contains several specific bundles of cipher documents (“Cifre Fasc[iculus/-i]”) that sounds like what I’m looking for. But then again, Meister was writing over a century ago and much may well have changed there: specifically, here’s a link to the best listing I could find for the pre-1535 part of the Potenze Estere archive, but note that there is no obvious cipher bundle or subset to be seen. And that would seem to be the end of the line – though I’d expect the 1455 letter from Naples listed by Smith is probably filed in the Napoli section of the Pot. Est. archive (which is more or less entirely arranged geographically).
At the end of all that, I don’t know whether I’m really close or really far away. Are the cipher bundles Meister referred to still in the Potenze Estere, and what do they contain? Or have they been moved, split, stolen or lost at some point during the last century? Regardless, where do I need to go to see them and what should I ask for? Any pointers you can turn up to help me answer these questions would be much appreciated! [Please leave comments on the page below, or email me at the normal address]. Thanks!
Update: I subsequently found a more detailed listing on p.927 of this sizeable inventory: it says that the Atti Ducali (1392-1535) section of the Archivio Sforzesco contains “Cancelleria segreta 1450-1535, scatole 11. Raccolta di documenti relativi all’attività quotidiana della cancelleria: sommari, cifrari, occorrenze (carta, inchiostro ecc.), archivio, documenti relativi alla biblioteca del castello di Pavia.” So perhaps the cipher documents Meister saw were later moved over to this Atti Ducali section?
Alternatively, the Carteggio Sforzesco’s Potenze Sovrane archive also holds a section marked “Cancelleria segreta – Chiavi e cifrari (scatt. 1591, 1597 – 1598)”, which is what Lidia Cerioni relied on for her book “La diplomazia sforzesca”, and might instead be what I’m looking for (it’s hard to tell). Oh, and just a few bundles away, the same archive has the intriguing-sounding scat. 1569: “Miscellanea, astrologia, occultismo, superstizione etc.” Really, what historian of mysteries could resist sneaking a peek? 😉