Master Spy or News Guy: Introduction
July Miniseries on Medieval and Renaissance Espionage
Introduction:
We hereby declare the month of July 2025, Espionage Month!
As we begin to discuss Medieval and Renaissance espionage, the reader’s imagination may conjure memories of the shadowy Game of Thrones characters Lord Varys or his less-stately rival; Littlefinger. Fans of Sherlock Holmes might even imagine the super sleuth’s infamous band of Irregulars. When it comes to the world of early modern espionage, none of these relations would be far off the mark. To understand what gives certain Medieval, Renaissance or fantasy characters this almost superhuman sense of foresight and cognition, we're going to explore some historical exemplars that illuminate the mysterious world of statecraft.
Espionage is defined as, “the practice of spying or using spies to obtain information about the plans and activities especially of a foreign government or a competing {enterprise}.” The key being the act of obtaining information. Sun Tzu, the 4th Century BC Martial Theorist, in his work the Art of War states, “One who knows the enemy and knows himself will not be endangered in a hundred engagements.”1
Using spys to attain information is an age-old practice. The Biblical story of Joshua and Caleb which likely took place around 1445 BC, located in the book of Numbers; chapters 13-14, details twelve Israelite spies who are tasked with sneaking into the land of Canaan, and returning with an assessment of the geography, demographics, population, and resources of the Promised land.2
As we’ll learn, the practice of espionage doesn’t always involve spies, secret agents or shaken martinis. In a world without digital technology and global conglomerate news networks, sometimes simply attaining knowledge of what was going on in a given location was half the battle, while other times having knowledge of something more intimate or personal could be used as a weapon or an intimidation tactic.
Historians generally can’t agree on when the first ‘official’ western state-run intelligence service was born. The Egyptians had extensive spy networks and intelligence gathering capabilities, the Romans had the Frumentarii, while in Medieval Georgia they had the Mstoviaris, yet many modern scholars tend to point to the Venetian Republic in the late 15th century or early 16th century as the birth of the practice.
In truth, it doesn’t really matter. People have always valued information as a resource, and the great lengths they have gone to get that information is what truly captivates our imaginations. Like Adam and Eve, the allure of the fruit from the tree of knowledge has driven man to depths of our depravity, the height of creativity, and yielded some truly remarkable stories.
Late Medieval to Early Renaissance Espionage:
So, what do we know about Medieval practices of espionage? Quite a bit actually, sometimes all you have to do is read between the lines. For example, the Duchy of Milan had some fairly influential ways-and-means of conducting espionage. While we don’t know how centralized or tied to the Dukedom this practice was, because it's never overtly discussed, the actions of the Milanese under Gian Galeazzo Visconti were always very well informed, and the extents to which the Duke and his agents were willing to go to preserve the Visconti legacy were legendary.
A great example that highlights this idea of ‘reading between the lines’ comes in 1401, when Giovanni Bentivoglio, the new ruler of the strategically important city of Bologna, was debating between taking Gian Galeazzo Visconti’s offer of allegiance with Milan or joining the anti-Visconti league with their rivals, the Florentines.
After Pietro Colte; the Milanese diplomat who was charged with extending the Duke’s offer to Giovanni, left Bologna for Milan to attend to matters of state, the Florentine diplomats swept in and started bribing members of Giovanni’s inner circle to influence his decision in their favor.3
Now—Giovanni had gone into closed council, only letting a handful of his most trusted officials advise his forthcoming decision. The Florentines knew this, because they had diplomats in Bologna, namely: Rineri Alberi, Bartolomeo da Pistoia, and Ricardo di Donato Acciaivoli. These men pinpointed Giovanni’s advisor, Antonio Guidotti, as the most sympathetic to their cause. So, they fed him information about the Florentines prospective alliance with the Holy Roman Emperor, Rupert I, and bribed him with a considerable sum of 4,000 ducats.4
Gudotti’s influence was enough to sway Giovanni’s decision, and he agreed to join the anti-Visconti league. When Pietro Colte returned to Bologna to retrieve Giovanni’s answer and was informed of his decision, he turned to Guidotti, put his hand on his shoulder and said, “Remember Antonio, that the four thousand ducats which you received are the reason why Giovanni failed in his faith to my Lord, and allied himself with the Florentines, and did not want to subscribe, for which both of you will soon find regret.”5
That's one hell of a mic-drop that really highlights the power and reach of the Milanese information gathering network. This revelation not only showed the power of the Milanese state, it undermined Giovanni’s faith in his trusted council and made him second guess the authenticity of his decision.
How could Colte have known about the secret bribe?
We’ll get into that, but before we do, let's look at a few more examples from this time period.
The Milanese weren't the only Medieval Italian state with sophisticated information gathering capabilities. While Alberi, Pistoia, and Acciaivoli were in Bologna securing Giovanni Bentivoglio’s allegiance, another Florentine diplomat by the name of Bonaccorso Pitti went to Germany to complete the negotiations between the Italian anti-Visconti league and the Holy Roman Emperor, Rupert I.
Initially, the German officials told the Florentine ambassadors that it would take a beleaguering sum of 500,000 florins to mobilize the Imperial princes—roughly 200,000 florins more than the Florentines were willing to pay.6 That was, until—during the negotiations, Milanese agents allegedly bribed the Emperor's personal physician to assassinate Emperor Rupert with a poisoned enema. A plot that was foiled by the astute Pitti, who conveniently saw a suspicious courier talking to the emperor's physician in the palatial gardens. An event which—when fully investigated—inspired Rupert to take the Florentines original offer of 200,000 Florins with 50,000 florins in advance; to be delivered in two installments along their campaign route into Italy—first in Germany then in Venice.7
Now, we can look at this one of two ways, either the Florentines set-up Rupert's physician to coerce Rupert into accepting their offer, or the Duke of Milan was a hairs breadth from whacking one of most powerful leaders in Medieval Europe. Either way, it's spectacular.
But it's not this moment that stands to highlight the depth and breadth of state guided intelligence gathering in Medieval Europe, it's what happens next.
In order to facilitate the transfer of the 25,000 Florin advance required to get the Imperial forces moving, Pitti had to travel over 500 miles across hostile territory, southwest to Florence, northeast to Padua, then due north to Augsburg. After his treacherous trek, he decided to go to Venice to see that the second installment of 25,000 florins was delivered safely, but on his way through Friuli he stopped at an inn in Venzone, where he was approached by a spice merchant from Siena with whom he was on familiar terms.8
This spice merchant informed Pitti that his life was in danger. Pitti records the conversation like this:
“The evening of my arrival in Venzone, I was visited by a man from Siena with whom I was on familiar terms, for I had gone to the spice shop that he kept there several times when passing through that town. He told me that he had learned of a plot to capture me on the road when I set out on the following day. This plot had been put together by a secret agent of the Duke of Milan, a man called Fra Giovanni Decani, who had promised the lord of Prampergh 4,000 gold ducats if he would hand me over to him. This Prampergh had promised to do so, under the guise of a reprisal against the Florentines. I asked the Sienese man if I could trust the innkeeper where I was staying. He said that I surely could.
So at about four in the morning I mounted my horse, and took with me the innkeeper and one of his servants so that I would not get lost, for I kept off the main road to Portogruaro. Without stopping to eat or drink, I reached Portogruaro, which is a journey of about 40 miles. There I boarded a ship and set out for Venice. I sent my horses to Padua {1402}. Later, after the death of the Duke of Milan, I encountered that same Fra Giovanni in Bologna, and he confessed to me that the story of the plot to capture me was true.”
—Benedetto Pitti; Branca, pg. 345-346
The nameless Sienese spice merchant who Pitti met in Venzone was probably a Florentine asset. This is indicated by their familiarity, and the fact that Pitti gave such a vague description of who he was. On the other hand, through this story also get to learn the name of one of the shadowy Milanese secret agents—a friar by the name Giovanni Decani. A man who Pitti later confronts in Bologna during the hectic feud over the inheritance of Gian Galeazzo Visconti’s expansive dominion.
What this story stands to highlight is that espionage and statecraft through government officials—be they diplomats or spies—was very real in the late Medieval world. Yet, what these stories fail to highlight is how this spy craft and intelligence gathering was done. To better understand the world of late Medieval and early Renaissance espionage, our new series, Master Spy or News Guy, is going to examine the lives of three key figures from the mid-15th century to the early-16th century. Namely, Benedetto Dei of Florence, Ser Cola di Ascoli of Bologna, and Marino Sanuto of Venice.
It's through the lives of three men that we hope to answer the question of how these acts of intelligence gathering were conducted, in order to afford the reader an unprecedented insight into the world of Medieval and Renaissance espionage.
Join us on our month long journey through this shadowy world full of assassin's, double agents and spies by signing up for our mailing list—its free. If you'd like to support us financially, we'd be eternally grateful. Your contributions go towards helping us buy resources to put together amazing stories like these.
Works Cited:
Branca, Vittore. Merchant Writers: Florentine Memoirs from the Middle Ages and Renaissance. United Kingdom, University of Toronto Press, 2015. eBook.
Ghirardacci, Cherubino. Della Historia Di Bologna. Volume 2. Italy, Giovanni Rossi, 1657.
Wikipedia contributors. (2025b, June 30). History of espionage. Wikipedia. https://en.wikipedia.org/wiki/History_of_espionage
Numbers 13-14 (NIV). (n.d.). Bible Gateway. https://www.biblegateway.com/passage/?search=Numbers%2013-14&version=NIV
Wikipedia, History of Espionage
Efforts to use espionage for military advantage are well documented throughout history. Sun Tzu, 4th century BC, a theorist in ancient China who influenced Asian military thinking, still has an audience in the 21st century for the Art of War. He advised, "One who knows the enemy and knows himself will not be endangered in a hundred engagements."[5] He stressed the need to understand yourself and your enemy for military intelligence.
Holy Bible (Bible Gateway), Numbers 13-14
Exploring Canaan
13 The Lord said to Moses, 2 “Send some men to explore the land of Canaan, which I am giving to the Israelites. From each ancestral tribe send one of its leaders.”
3 So at the Lord’s command Moses sent them out from the Desert of Paran. All of them were leaders of the Israelites. 4 These are their names:
from the tribe of Reuben, Shammua son of Zakkur;
5 from the tribe of Simeon, Shaphat son of Hori;
6 from the tribe of Judah, Caleb son of Jephunneh;
7 from the tribe of Issachar, Igal son of Joseph;
8 from the tribe of Ephraim, Hoshea son of Nun;
9 from the tribe of Benjamin, Palti son of Raphu;
10 from the tribe of Zebulun, Gaddiel son of Sodi;
11 from the tribe of Manasseh (a tribe of Joseph), Gaddi son of Susi;
12 from the tribe of Dan, Ammiel son of Gemalli;
13 from the tribe of Asher, Sethur son of Michael;
14 from the tribe of Naphtali, Nahbi son of Vophsi;
15 from the tribe of Gad, Geuel son of Maki.
16 These are the names of the men Moses sent to explore the land. (Moses gave Hoshea son of Nun the name Joshua.)
17 When Moses sent them to explore Canaan, he said, “Go up through the Negev and on into the hill country. 18 See what the land is like and whether the people who live there are strong or weak, few or many. 19 What kind of land do they live in? Is it good or bad? What kind of towns do they live in? Are they unwalled or fortified? 20 How is the soil? Is it fertile or poor? Are there trees in it or not? Do your best to bring back some of the fruit of the land.” (It was the season for the first ripe grapes.)
21 So they went up and explored the land from the Desert of Zin as far as Rehob, toward Lebo Hamath. 22 They went up through the Negev and came to Hebron, where Ahiman, Sheshai and Talmai, the descendants of Anak, lived. (Hebron had been built seven years before Zoan in Egypt.) 23 When they reached the Valley of Eshkol,[a] they cut off a branch bearing a single cluster of grapes. Two of them carried it on a pole between them, along with some pomegranates and figs. 24 That place was called the Valley of Eshkol because of the cluster of grapes the Israelites cut off there. 25 At the end of forty days they returned from exploring the land.
Report on the Exploration
26 They came back to Moses and Aaron and the whole Israelite community at Kadesh in the Desert of Paran. There they reported to them and to the whole assembly and showed them the fruit of the land. 27 They gave Moses this account: “We went into the land to which you sent us, and it does flow with milk and honey! Here is its fruit. 28 But the people who live there are powerful, and the cities are fortified and very large. We even saw descendants of Anak there. 29 The Amalekites live in the Negev; the Hittites, Jebusites and Amorites live in the hill country; and the Canaanites live near the sea and along the Jordan.”
30 Then Caleb silenced the people before Moses and said, “We should go up and take possession of the land, for we can certainly do it.”
31 But the men who had gone up with him said, “We can’t attack those people; they are stronger than we are.” 32 And they spread among the Israelites a bad report about the land they had explored. They said, “The land we explored devours those living in it. All the people we saw there are of great size. 33 We saw the Nephilim there (the descendants of Anak come from the Nephilim). We seemed like grasshoppers in our own eyes, and we looked the same to them.”
The People Rebel
14 That night all the members of the community raised their voices and wept aloud. 2 All the Israelites grumbled against Moses and Aaron, and the whole assembly said to them, “If only we had died in Egypt! Or in this wilderness! 3 Why is the Lord bringing us to this land only to let us fall by the sword? Our wives and children will be taken as plunder. Wouldn’t it be better for us to go back to Egypt?” 4 And they said to each other, “We should choose a leader and go back to Egypt.”
5 Then Moses and Aaron fell facedown in front of the whole Israelite assembly gathered there. 6 Joshua son of Nun and Caleb son of Jephunneh, who were among those who had explored the land, tore their clothes 7 and said to the entire Israelite assembly, “The land we passed through and explored is exceedingly good. 8 If the Lord is pleased with us, he will lead us into that land, a land flowing with milk and honey, and will give it to us. 9 Only do not rebel against the Lord. And do not be afraid of the people of the land, because we will devour them. Their protection is gone, but the Lord is with us. Do not be afraid of them.”
10 But the whole assembly talked about stoning them. Then the glory of the Lord appeared at the tent of meeting to all the Israelites. 11 The Lord said to Moses, “How long will these people treat me with contempt? How long will they refuse to believe in me, in spite of all the signs I have performed among them? 12 I will strike them down with a plague and destroy them, but I will make you into a nation greater and stronger than they.”
13 Moses said to the Lord, “Then the Egyptians will hear about it! By your power you brought these people up from among them. 14 And they will tell the inhabitants of this land about it. They have already heard that you, Lord, are with these people and that you, Lord, have been seen face to face, that your cloud stays over them, and that you go before them in a pillar of cloud by day and a pillar of fire by night. 15 If you put all these people to death, leaving none alive, the nations who have heard this report about you will say, 16 ‘The Lord was not able to bring these people into the land he promised them on oath, so he slaughtered them in the wilderness.’
17 “Now may the Lord’s strength be displayed, just as you have declared: 18 ‘The Lord is slow to anger, abounding in love and forgiving sin and rebellion. Yet he does not leave the guilty unpunished; he punishes the children for the sin of the parents to the third and fourth generation.’ 19 In accordance with your great love, forgive the sin of these people, just as you have pardoned them from the time they left Egypt until now.”
20 The Lord replied, “I have forgiven them, as you asked. 21 Nevertheless, as surely as I live and as surely as the glory of the Lord fills the whole earth, 22 not one of those who saw my glory and the signs I performed in Egypt and in the wilderness but who disobeyed me and tested me ten times— 23 not one of them will ever see the land I promised on oath to their ancestors. No one who has treated me with contempt will ever see it. 24 But because my servant Caleb has a different spirit and follows me wholeheartedly, I will bring him into the land he went to, and his descendants will inherit it. 25 Since the Amalekites and the Canaanites are living in the valleys, turn back tomorrow and set out toward the desert along the route to the Red Sea.[b]”
26 The Lord said to Moses and Aaron: 27 “How long will this wicked community grumble against me? I have heard the complaints of these grumbling Israelites. 28 So tell them, ‘As surely as I live, declares the Lord, I will do to you the very thing I heard you say: 29 In this wilderness your bodies will fall—every one of you twenty years old or more who was counted in the census and who has grumbled against me. 30 Not one of you will enter the land I swore with uplifted hand to make your home, except Caleb son of Jephunneh and Joshua son of Nun. 31 As for your children that you said would be taken as plunder, I will bring them in to enjoy the land you have rejected. 32 But as for you, your bodies will fall in this wilderness. 33 Your children will be shepherds here for forty years, suffering for your unfaithfulness, until the last of your bodies lies in the wilderness. 34 For forty years—one year for each of the forty days you explored the land—you will suffer for your sins and know what it is like to have me against you.’ 35 I, the Lord, have spoken, and I will surely do these things to this whole wicked community, which has banded together against me. They will meet their end in this wilderness; here they will die.”
36 So the men Moses had sent to explore the land, who returned and made the whole community grumble against him by spreading a bad report about it— 37 these men who were responsible for spreading the bad report about the land were struck down and died of a plague before the Lord. 38 Of the men who went to explore the land, only Joshua son of Nun and Caleb son of Jephunneh survived.
39 When Moses reported this to all the Israelites, they mourned bitterly. 40 Early the next morning they set out for the highest point in the hill country, saying, “Now we are ready to go up to the land the Lord promised. Surely we have sinned!”
41 But Moses said, “Why are you disobeying the Lord’s command? This will not succeed! 42 Do not go up, because the Lord is not with you. You will be defeated by your enemies, 43 for the Amalekites and the Canaanites will face you there. Because you have turned away from the Lord, he will not be with you and you will fall by the sword.”
44 Nevertheless, in their presumption they went up toward the highest point in the hill country, though neither Moses nor the ark of the Lord’s covenant moved from the camp. 45 Then the Amalekites and the Canaanites who lived in that hill country came down and attacked them and beat them down all the way to Hormah.
Ghirardacci, Pg.522
Fiorentini, intesa la risolutione fatta tra il Duca di Milano, e Bentivoglio, si per rallegrarsi seco, come anco, per invitario ad entrare seco in lega, con fargli offerta, che si come sempre erano stati fedeli amici de' Bolognesi, anco di presente, come tali gli offerivano ogni aiuto di gente, e di danari. A' quali Giovanni rispose.
Ghirardacci, Pg.522-523
E che bene faccia loro intendere, che se prima l'banessero ricercato, di buona voglia gli havrebbe contentati. A questa risposta, non si persero d' animo gli Oratori Fiorentini, anzi appoggiati a maggior speranza, si rivolsero a varij intercesori, e fra gli altri ad Antonio Guidotti, ch' era l'anima instessa del Bentivoglio, & huomo nella Citta di grandissima auttorita, a cui secero dono di quattro mila Ducati d' oro, accioche si adoperasse in modo, che l'accordo tra il Duca di Milano, e Giovanni Bentivoglio non seguisse piu oltre, ma che adherisse all'mutio de Fiorentini. Ora Antonio allettato dall osserta del danro parlo con Giovanni, e per disporlo a questo satto, gli addusse di molte ragioni, e gli dimostro apertamente, che non doueva collegarsi con il Duca di Milano, percioche Giovan Galeazzo cio faceva con sicuro disegno di prima opprimere la Toscana, e poi havere il dominio di Bologna, e che per questo, e non per altrocercava di collegarsi con esso lui. Queste parole posero Giovanni in tanto sospetto, che non spaeva, che consiglio pigliare, & essendo stato tutto un giorno, & una notte sopra se stesso, finalmente determino di consigliari con li suoi amici, e segreti Consiglieri, li quali accostandosi al giuditio del Guidotti, secero si, che Giovanni mancando al Duca, con li Fiorentini si collego in questo modo.
Ghirardacci, Pg. 523
Udendo l'Oratore la repulsa del Bentivoglio, come quello, che del trattato de' Fiorentini con il Guidotti era Capace, ripieno di giusto sdegno, con la mano toccando la spalla ad Antonio, che quiui era presente, disse.
Ramentari Antonio, che li quattro mila scudi, che bai ricevvti, sono la cagione, che Giovanni ba mancato della sua fede al mio Signore, e si e collegato con Fiorentini, e non ha voluto sottoscrivere, di che amendue tosto ve ne pientirrete.
Branca, pg 339-340
Ingolstadt and then Hamburg,100 where we found the newly elected Emperor. After I had presented the obeisance and compliments of our city, I said that whenever it should please His Majesty, I would expound my embassy to him, either privately or publicly, whichever he preferred. He received us readily, saying that he would inform us when he was ready to hear our message. At his expense, he had us lodged in a very fine house, where we were honourably waited on by his own servants. On the second day, he sent for us, and asked me to deliver my message in the presence of about eight members of his council. I delivered it, and though I said that we would be willing to make him a payment, I did not name the amount. He responded that he would appoint delegates to negotiate with us, which he did. During the negotiations, they asked us what amount our city would be willing to pay. I replied that they should ask for what they thought was appropriate, and they answered that the Emperor would need our city to help him with 500,000 florins, if he were to come to Italy that year. I said that I wished to respond to that point in the Emperor’s presence. We went before him, and I said, “Your majesty, your delegates have asked me for an astoundingly large sum; and it seems to us that this is a polite way of refusing to come to Italy, for you must be well aware that it would be impossible for our city to pay such a sum.” He said that I was right – he did not want to go to Italy that year, because he didn’t have the money; for the 300,000 florins he had gotten before he was elected had all been spent for the two sessions of the imperialdiet101 that he had held after his election. He said that if we could wait another year, he would have more money, and would not have to ask us for so much; but if we still wished him to come that year, we would have to bear most of the expense.
Branca, pg. 340-341
While we were still waiting for a reply from Florence, it happened that we dined with the Emperor in one of his gardens, and I, having noticed that he took no precautions against poison, said to him, “Your Highness, it seems that you are not aware of the perfidity of the Duke of Milan; for if you were, you would take greater care for your safety than you do. For you may be certain that when he hears that you are resolved to cross into Italy, he will do his utmost to have you killed or either by poison or stabbing.” His countenance changed entirely, and he crossed himself, saying, “Could he be so perfidious as to attempt to have me killed, when I have not declared war on him, nor he on me? I find this difficult to believe; nevertheless, I will follow your advice and take great care.” And this he did. And among other things, on account of the suspicion that I aroused in him, whenever he saw someone whom he did not know, he immediately wanted to know what that person was up to. On one occasion, when he and we, who were continually with him, went to a fine estate of his near Hamburg to hunt, the Emperor noticed a man dressed as a courier; he had him summoned and questioned him. The man said that he was on his way to Venice, and that he had come to that place solely to see the Emperor and to be able to give him news of him at Venice. The Emperor ordered one of his Knights to take the man to his chamber and to keep him there until he returned from mass. When he returned, the courier confessed to him that he had come from Pavia carrying a letter to the Emperor’s physician from Maestro Piero da Tosignano, the physician of the Duke of Milan, and that he had carried such letters on other occasions. The Emperor read the letter, and sent for his physician, whose name was Master Herman, who had been a pupil of Master Piero da Tosignano. In short, the physician confessed that he was to have poisoned the Emperor with a clyster, for which he was to receive 15,000 ducats, 5,000 to be paid in Mainz and 10,000 in Venice.
Branca, pg. 340-342
And now you hear how they have failed me. Therefore I entreat you, Bonaccorso, make haste to go and recount what has happened to my devoted sons in the Florentine Seignory, and entreat them to salvage my honour and their own interests if they want me to bein Lombardy at the appointed time. Tell them that in order for me to depart from Augsburg, I need them to advance me at least 25,000 gold ducats of the promised amount.” I strongly resisted going to Florence, asserting that it would be safer and quicker to send duplicate letters. But the Emperor would not be persuaded by any argument that I should not go, so I decided to depart, fearing that if I did not, he would not come to Italy that year. I left Heidelberg on the 18th of July and arrived in Padua in 12 days, which is a journey of more than 500 miles. The lord of Padua was astonished that I had been able to arrive in such a short time; he wouldn’t have believed it if it hadn’tbeen for a letter that I brought him from the Emperor. I had had a fever for 4 days when I left Padua, and when I arrived in Rovigo I had to stay in bed for a day because my fever was so high I could not ride. On the second day, I got on a boat which took me by way of various canals to the Po River and from there to Francolino, where I again took horse and rode to Messer Egano’s home at Poggio,104 where I spent the night.
Looking forward to this series, especially anything on Sanuto (I just finished reading Venice's Secret Service: Organising Intelligence in the Renaissance by Ioanna Iordanou, which I had mixed feelings about).