Francesco (Cicco) Simonetta (1410 – 30 October 1480) was an Italian Renaissance statesman who composed an early treatise on
cryptography
Cryptography, or cryptology (from "hidden, secret"; and ''graphein'', "to write", or ''-logy, -logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of Adversary (cryptography), ...
.
Biography
Francesco, nicknamed Cicco, was born in
Caccuri,
Calabria
Calabria is a Regions of Italy, region in Southern Italy. It is a peninsula bordered by the region Basilicata to the north, the Ionian Sea to the east, the Strait of Messina to the southwest, which separates it from Sicily, and the Tyrrhenian S ...
, and received a fine education. He studied
Latin
Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...
,
Greek,
Hebrew
Hebrew (; ''ʿÎbrit'') is a Northwest Semitic languages, Northwest Semitic language within the Afroasiatic languages, Afroasiatic language family. A regional dialect of the Canaanite languages, it was natively spoken by the Israelites and ...
, and other languages and graduated in civil and canonic law, presumably in
Naples
Naples ( ; ; ) is the Regions of Italy, regional capital of Campania and the third-largest city of Italy, after Rome and Milan, with a population of 908,082 within the city's administrative limits as of 2025, while its Metropolitan City of N ...
.
As a young man, he entered the service of the Sforza family as a secretary to
condottiero
Condottieri (; singular: ''condottiero'' or ''condottiere'') were Italian military leaders active during the Middle Ages and the early modern period. The term originally referred specifically to commanders of mercenary companies, derived from the ...
Francesco Sforza and rapidly rose to the top of the administration. He was soon placed in charge of the city of
Lodi.
In 1441,
Francesco Sforza married
Bianca Maria Visconti (1425–1468), the illegitimate daughter of
Filippo Maria Visconti
Filippo Maria Visconti (3 September 1392 – 13 August 1447) was the duke of Duchy of Milan, Milan from 1412 to 1447. Reports stated that he was "paranoid", but "shrewd as a ruler." He went to war in the 1420s with Romagna, Republic of Florenc ...
, 3rd Duke of Milan. On Filippo's death (1447), the so-called
Ambrosian Republic had been set up in
Milan
Milan ( , , ; ) is a city in northern Italy, regional capital of Lombardy, the largest city in Italy by urban area and the List of cities in Italy, second-most-populous city proper in Italy after Rome. The city proper has a population of nea ...
by the patrician families. In 1450,
Francesco Sforza, backed by the Venetians, laid siege to Milan to combat the aristocrats. The city surrendered after eight months and Francesco made himself ''Capitano del popolo''. He was proclaimed
duke
Duke is a male title either of a monarch ruling over a duchy, or of a member of Royal family, royalty, or nobility. As rulers, dukes are ranked below emperors, kings, grand princes, grand dukes, and above sovereign princes. As royalty or nobi ...
by the people and by the right of his wife.
Simonetta was nominated "golden knight" and entered the ducal chancellery. This appointment was the beginning of his undisputed domination of the political situation for thirty years. As a reward for his services, he was given the fief of
Sartirana, in
Lomellina, which he administered with competency and care. He soon became a member of the Secret Council. When he married Elisabetta Visconti in 1452 his fame was widespread.
In 1456, he received the honorary citizenship of
Novara, which was later followed by those of
Lodi and
Parma
Parma (; ) is a city in the northern Italian region of Emilia-Romagna known for its architecture, Giuseppe Verdi, music, art, prosciutto (ham), Parmesan, cheese and surrounding countryside. With a population of 198,986 inhabitants as of 2025, ...
. In 1465, he wrote the ''Constitutiones et Ordines'' as a contribution to a better organization of the chancellery, over which he now had complete control.
At the death of
Francesco Sforza (1466), his son
Galeazzo Maria succeeded him. His mother Bianca Maria and the other influential families did not approve of his capricious conduct of state affairs, but Simonetta sided with Galeazzo.
In 1474 Simonetta wrote his ''Rules for Decrypting Enciphered Documents Without a Key'', presumably for use by his collaborators, although no evidence exists of actual utilization of these rules in the field.
In 1476, Galeazzo was assassinated and was succeeded by his 7-year-old son
Gian Galeazzo. His tutor was his mother,
Bona of Savoy. In this period of unrest, Simonetta's diplomatic activity was intense. He manoeuvred to maintain stability in the Milanese state during the endemic conflicts between
Guelphs
The Guelphs and Ghibellines ( , ; ) were Political faction, factions supporting the Pope (Guelphs) and the Holy Roman Emperor (Ghibellines) in the Italian city-states of Central Italy and Northern Italy during the Middle Ages. During the 12th ...
,
Ghibellines and the various wars and interstate alliances.
The next year he became ducal secretary, with the powers of a prime minister. Simonetta's power provoked the hatred of
Ludovico il Moro (1452–1508), one of the younger brothers of Galeazzo, who plotted to seize the duchy. The main obstacle to his project was the presence of Simonetta in the city government. After many personal vicissitudes, Ludovico managed to gain the confidence of the duchess and convinced her to arrest Simonetta.
He was accused falsely of
treason
Treason is the crime of attacking a state (polity), state authority to which one owes allegiance. This typically includes acts such as participating in a war against one's native country, attempting to Coup d'état, overthrow its government, spy ...
, imprisoned, and tortured in Pavia. His house and assets were pillaged, and he was
beheaded in the tower of the castle. His body was buried in the
cloister of Sant’Apollinare, outside the Milan city walls, to mark the end of his influence in Milanese politics.
During the Sforza rule, the duchy enjoyed years of prosperity and great expansion despite the political turmoil. Important buildings were erected in the cities; the farming of rice and the silk industry were introduced in agriculture. With the advent of printing, Milan had become a cultural centre unequalled in all of Europe, until it fell into foreign hands after the death of Ludovico il Moro.
Presently a fragment of his tombstone and the name of a narrow street in Milan are the only visible testimonials of Simonetta.
Decrypting rules
Simonetta has been described in the cryptological literature as an important cryptanalyst in consideration of his rules.
His work is in reality a collection of hints for solving ciphers that were rather old-fashioned at that time. Contemporary cipher clerks were well equipped to defy the tricks he described. Nomenclators were in general use, combining small codebooks and large substitution tables with homophones and nulls.
His cipher-breaking rules are applicable to dispatches with word divisions, without homophones, nulls or code words. He says nothing of polyalphabetic substitution or the existence of nomenclators. His notes were anticipated by
Leon Battista Alberti
Leon Battista Alberti (; 14 February 1404 – 25 April 1472) was an Italian Renaissance humanist author, artist, architect, poet, Catholic priest, priest, linguistics, linguist, philosopher, and cryptography, cryptographer; he epitomised the natu ...
in his theoretical, but more comprehensive, treatise
''De Cifris'', which earned him the title of Father of Western Cryptology.
It was only a century later that a scientific treatise entirely devoted to cryptanalysis was written by the French mathematician
François Viète. Simonetta might have been involved in cipher work in his early career, but no evidence of such activity has been found.
References
* Buonafalce, A. “Cicco Simonetta’s Cipher-Breaking Rules”, ''Cryptologia'' XXXII: 1. 62–70. 2008.
* Colussi, P. ''Cicco Simonetta, Capro Espiatorio di Ludovico il Moro''. Storia di Milano Vol. VII, Milano 1957.
* Natale, A. R. Ed. ''I Diari di Cicco Simonetta (1473–76 and 1478''), Milano 1962.
* Perret, P.-M. "Les règles de Cicco Simonetta pour le déchiffrement des écritures secrètes" Paris ''Bibliothèque de l’École des chartes'' 51 (1890) 516–525.
* Pesic, P. “François Viète. Father of Modern Cryptanalysis—Two New Manuscripts”, ''Cryptologia'' XXI: 1. 1-29. 1997.
* Sacco, L., "Un Primato Italiano. La Crittografia nei Secoli XV e XVI", ''Bollettino dell'Istituto Storico e di Cultura dell'Arma del Genio'', Roma, December 1947.
* Smith, Rev. J., Ed. ''The Life, Journals and Correspondence of Samuel Pepys''. 275. 1841.
External links
*
{{DEFAULTSORT:Simonetta, Francesco
1410 births
1480 deaths
People from the Province of Crotone
15th-century Italian politicians
Medieval cryptographers
Italian cryptographers
People executed in the Holy Roman Empire by decapitation
History of Milan
Executed Italian people
People executed by the Duchy of Milan
15th-century executions