“Secret Correspondence” in Habsburg–Ottoman Communication in the First Half of the Seventeenth Century

 

János Szabados
University of Szeged
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Hungarian Historical Review Volume 12 Issue 2  (2023):3–36 DOI 10.38145/2023.2.194

For the Habsburg Monarchy in the seventeenth century, it was very important to collect, send to Vienna, and evaluate up-to-date information on the Ottoman Empire. Following the Long Turkish War (1591/1593–1606), it was necessary in the 1620s to organize, alongside couriers and other channels of correspondence (e. g. the Venetian post), a cost-effective and sustainable system with which to transmit news and, in part, intelligence. In this essay, I present the historiography of the “institution” known as the “Secret Correspondence” and the history of the organization and reorganizations of the system. I also establish a typology of the people involved in the correspondence, namely 1) letter forwarders, 2) letter forwarders who also wrote secret reports, and

3) spies who wrote secret reports regardless of their location (in this case, the person was more important than the information). In the first half of the seventeenth century (1624 to 1658), the system of “Secret Correspondence” had to be reorganized several times (mostly due to lack of funds). In each case, the main challenge was to find and continuously employ the right people, so the role of the recruiter was also important. The political situation in the abovementioned period had an obvious impact on the functioning of the system, too. My research is based on documents from the Viennese archives (Österreichisches Staatsarchiv, Haus-, Hof-, und Staatsarchiv; Kriegsarchiv, Finanz- und Hofkammerarchiv), which have helped me to offer a more detailed and nuanced understanding of the “Secret Correspondence” than found in the existing secondary literature.

Keywords: Habsburg-Ottoman diplomacy, intelligence, flow of information, information channels, typology of the informants

Introduction

Interest among scholars in Habsburg–Ottoman diplomacy has increased in recent decades. The peaceful period of the first half of the seventeenth century (1606–1663) is of particularly strong interest.1 In this essay, I investigate a vital channel of communication between the Habsburg Monarchy and the Ottoman Empire, namely the institution known as the “Secret Correspondence” (Geheime Korrespondenz). The continuity of the correspondence between Vienna and Constantinople had a great impact on relations between the two empires. It was of primary importance for the Habsburgs mostly, as it helped them closely monitor the policies of the Ottoman Empire and have direct and prompt access to the relevant pieces of news and information with which to shape their European policy, especially during and after the Thirty Years’ War. In the discussion below, I look at the secondary literature on this “Secret Correspondence,” outline the history of its establishment in the first half of the seventeenth century (1623–1658), look at the historical and political context, and introduce the diplomats involved in its organization. Moreover, I examine the parallel information channels and establish a typology of those involved in the transmission of letters and intelligence. I also describe the roles of these actors in the network’s operation and offer some examples of how their activity as letter forwarders or spies impacted their careers. My intention is to offer a more nuanced understanding of how the Habsburg communications and intelligence system functioned in the Ottoman Empire and to demonstrate that the “Secret Correspondence” was primarily used as a form of infrastructure, which, of course, also made espionage more effective.

Historical and Political Context

The Battle of Mohács in 1526 determined the politics of the following decades, as the Habsburg Monarchy became a direct neighbor of the Ottoman Empire, which was expanding through the Kingdom of Hungary. The longer period of peace after 1568 provided an opportunity for secret diplomacy to develop,2 but the Long Turkish War at the end of the century (1591–1606) interrupted this process. The Peace of Zsitvatorok in 1606 provided a new possibility to resume peaceful diplomatic relations, especially during the Thirty Years’ War (1618–1648).3 Both empires were already entangled in conflicts in various theaters of war and were forced to maintain peace with each other, though this peace was fragile and had to be affirmed on several occasions (1615/1616, 1618, 1625, 1627, and 1642). After the Thirty Years’ War, the two empires did not start a new war with each other but rather extended the peace again in 1649.4 Each peace treaty was accompanied by a solemn grand embassy, but these embassies were not necessarily sent only on the occasion of a new affirmation of peace.5 The envoys (with the rank of ambassador or internuncius) also played a role in the organization and operation of the “Secret Correspondence,” but the actual operation was the responsibility of the “experts” in charge of the Aulic War Council (Hofkriegsrat) and the resident ambassadors in Constantinople. Nevertheless, for various reasons (for instance, the death of a member or changes in the underlying political situation), it became necessary to reorganize the system several times by the mid-seventeenth century (until 1658).

The Revolution of Communication in the Early Modern Period

The early modern period saw a revolution in communication that had less to do with the invention of printing and more with changes in infrastructure.6 The postal system developed rapidly, and this contributed to better and faster correspondence. In the Holy Roman Empire, the Thurn und Taxis family owned the post office as a fief. In the Hereditary Lands of the Habsburgs, the postal service belonged to the Paar family, although the institution of postmaster existed for a time in the Kingdom of Hungary as well.7 This system, with its very well-functioning infrastructure, enabled faster and easier communication, which also had a positive effect on European societies and cultures.8 Parallel to the official correspondence, there existed an unofficial form of communication, mostly conducted in ciphers (i.e., secret writings of various kinds) which was used to transmit important and non-public information.9 There is a very substantial literature on early modern intelligence.10 With regard to the Ottoman Empire, two works are worth highlighting. John-Paul Ghobrial has examined the complex flow of information in Constantinople, London, and Paris in the late seventeenth century,11 and Ioanna Iordanou has offered a thorough analysis of the extensive European and non-European (i.e. Ottoman Empire) intelligence network of Venice.12

In the discussion below, I examine another form of communication that was specifically established between Vienna, Constantinople, and most of the European areas of the Ottoman Empire, namely the so-called “Secret Correspondence.” Since a comprehensive reform of the postal system took place in the 1620s, it is reasonable to assume that the founding of the “Secret Correspondence” was also connected with this reform, though no sources have yet been found providing clear confirmation of this. One document makes clear the relevance of communication during the legation of envoy (internuncius) Johann Jakob Kurz von Senftenau (1623–1624), as Ferdinand II ordered the restoration of the post office in Altenburg/Mosonmagyaróvár, Raab/Győr, and Komorn/Komárom and Révkomárom/Komárno in the autumn of 1623.13 It must be added, however, that in the case of the Imperial Post and the Post of the Hereditary Lands of the Habsburgs, they were official and public structures. In contrast, the “Secret Correspondence” was in principle an unofficial channel of communication.

The Secondary Literature on and Terminology Concerning the “Secret Correspondence”

In contrast to what has been stated in the secondary literature, in my view, the network of “Secret Correspondence” primarily provided an infrastructure for more fluid communication between Vienna and Constantinople, and this infrastructure was always dynamically adapted to the circumstances. Some elements of the system have been addressed in the scholarship, but the mechanisms of its operation in the first half of the seventeenth century have not yet been explored in detail, and this has led to misunderstandings in the interpretation of certain sources. The system of “Secret Correspondence” was already known to scholars in the early twentieth century. Numismatist Carl von Peez drew attention to the work of correspondents in Buda, Belgrade, and Sofia who were active after 1665, but he did not systematically explore the function of the system in the second half of the seventeenth century.14 This applies to the earliest Hungarian scholars on the subject. Sándor Takáts and Gyula Erdélyi mentioned the actors in the system by name in their essays, and they emphasized that the appearance of foreign (i.e., non-Hungarian) participants crowded Hungarians out of the intelligence system.15 Peter Meienberger also devoted a few pages in his book to the “Secret Correspondence,” and he made important observations about the operation of the system and treated it separately from the intelligence service.16 The establishment of the system was first outlined by István Hiller, who based his conclusions on the mission of the aforementioned Johann Jakob Kurz von Senftenau. Hiller interpreted the “Secret Correspondence” as an intelligence system, but his findings prompted certain points that need further clarification, including, for instance, the function(s) of this system.17 Dóra Kerekes examined in more detail the correspondents of the second half of the seventeenth century, focusing on the role of the Orientalische Handelskompanie (Oriental Trade Company) in the “Secret Correspondence.”18 She also explored the activities of the interpreters (in her terminology, the “Secret Correspondents”) who resided in Constantinople during the Great Turkish War (1683–1699), from where they wrote and sent secret reports.19 On the basis of her research on the abovementioned period, Kerekes concluded that the “Secret Correspondence” could be regarded as an intelligence system in the modern sense.20 However, the system of “Secret Correspondence” seems to have been more complex than mere espionage and can be seen rather as an intelligence and messaging system. I will explore this in more detail below.

The Reasons for Organizing the System and the Manner in which it was Implemented

During the second campaign (1623–1624) of Transylvanian prince Gábor Bethlen (1613–1629), which he launched against the Habsburgs in the Kingdom of Hungary five years after the outbreak of the Thirty Years’ War,21 Johan Jakob Kurz von Senftenau, Habsburg envoy to the Ottoman Porte, was commissioned with the establishment of a new system of communication. The aim was pragmatic: to replace the flow of information, which had been weakened by Bethlen’s attacks, with a financially more optimal system of mail transmission (which could be maintained between Belgrade and Constantinople for less than 500 talers a year) that would be less dependent on Venice.22 In accordance with his instructions, the diplomat recruited suitable people, primarily merchants in Buda, Belgrade, and Sofia. They were contracted to forward letters between Vienna and Constantinople twelve times a year for a certain sum. This solution was indeed more affordable since it cost 240 talers per occasion to send couriers.23 On his return journey from Constantinople, Kurz recruited people whom he thought qualified for the task and who were willing to undertake it. Thus, Hironimo/Girolammeo Grassi (240 talers)24 in Sofia, Matteo Sturani25 (240 thalers) in Belgrade, and Giovanni Pellegrini (160 talers) in Buda took on the task of forwarding the letters, and thus the costs in Belgrade and Sofia were kept below the prescribed 500 thalers.26 They were merchants from Ragusa (see table), and Grassi and Sturani had provided their services to the Habsburgs before.27 The operation of that newly established correspondence was presumably the responsibility of war councilor Count Michael Adolf Althan,28 secretary of the Aulic War Council and later also a war councilor Gerhard von Questenberg,29 and resident ambassador of Constantinople Sebastian Lustrier (1623–1629).30

Typology of Members of the “Secret Correspondence”

Before presenting the functioning of the system, I offer first an outline of the terms used to refer to participants in the system. My intention is to clarify the roles these actors played, at least to the extent possible on the basis of the sources. The meaning of the term “correspondent” as used in the sources seems problematic. It may have referred to someone who was both a “correspondent” or “spy” and a “letter forwarder.”31 Indeed, within the system, several functions can be clearly distinguished, even if some of terms sometimes seem ambiguous. Accordingly, for those who merely forwarded letters, I suggest the term letter forwarder. Those who primarily reported on important events should be called spies. The last category, and the most difficult to define, is those who forwarded letters and wrote spy reports. In their case, two subcategories can be distinguished, namely people who primarily spied and sometimes also forwarded letters and people who were contracted primarily to forward letters, but in some cases wrote secret reports as well. These people also received a salary from the Court Chamber, unlike, for example, Marino Tudisi, who was recruited as a private servant of Count Althan.32

Attempts at Reorganization between 1628 and 1658

The “Secret Correspondence” needed to be reorganized several times in the first half of the seventeenth century. Lustrier, the Habsburg resident ambassador at the Porte who was most interested in uninterrupted communication between the two powers, frequently used the new channel, but he also warned the court of the shortage of funds due to the war.33 By the end of the 1620s, after the negotiators of the two empires had successfully agreed to extend the peace in 1627 in Szőny, the system was in dire need of reorganization.34 The task of dispatching the ratification to Constantinople was entrusted to Baron Johann Ludwig von Kuefstein, a recent convert to Catholicism, who entered the Habsburg–Ottoman diplomacy as a homo novus.35 He was also instructed, however, to reorganize the “Secret Correspondence.”36 He was prepared for his journey by Michael Starzer (1610–1622), the former agent at the Porte, and Johann Rudolf Schmid (1629–1643), a former Ottoman captive and the next resident ambassador.37 However, due to the lack of a suitable “specialist,” only the aforementioned Marino Tudisi accompanied him as an expert.38 Presumably because of his earlier studies in Italy, Kuefstein preferred the Ragusan citizens as future letter forwarders, too. He enlisted the help of Tudisi on his way to the Sublime Porte. In Belgrade, he recruited Tomaso Orsini for Buda, Francesco Vlatchy/Vlatky for Belgrade, and Marco Cavalcanti for Sofia.39 During his stay in Constantinople, however, Kuefstein preferred sending letters through his courier, Wolf Leuthkauff, which obviously had an impact on the frequency of the correspondence.40 Orsini, for example, proved unreliable,41 thus Kuefstein had to use other channels and modify previous arrangements on the return journey. As a result, he first made an agreement in Sofia with a person called Stefano Vukovicz (Vuković).42 Nevertheless, in Belgrade the aforementioned Vlatchy/Vlatky then undertook to organize the entire correspondence between Constantinople and Komárom, and he himself proved ready to write secret reports. This is probably why he received the rather high sum of 700 thalers.43 In Komárom, Kuefstein entered into a contract with János Papp to transmit letters for 100 thalers a year.44 Thus, Kuefstein succeeded in his mission to reorganize the “Secret Correspondence.”

In the years that followed, the new resident ambassador Schmid was responsible for controlling the system, which he did together with the imperial interpreter in Vienna, Michel d’Asquier (1625–1664).45 Schmid also made use of the “Secret Correspondence,” but he sometimes bribed couriers en route to Buda and used the Transylvanian and Venetian postal services as well.46 Little is known about the identity of the letter forwarders from this period (see table). Since pieces of news from the Middle East were very important for the court because of the Thirty Years’ War, Schmid also recruited Francesco Crasso/Grassi, a doctor who had previously worked in Buda and was also of Ragusan origin.
Dr. Grassi was primarily an intelligence agent (spy), and not only for the Habsburgs, of course.47 Schmid also relied on the services of Andrea Scogardi (originally Johann Andersen Skovgaard), also a doctor, who, after his resettlement, kept the resident ambassador regularly informed about Moldavian and Transylvanian affairs.48 Johann Rudolf Puchheim, the grand ambassador assigned to the Porte in 1634, also tried to recruit new people, but there are no relevant data on the long-term impact of this.49 Because of financial problems, when they submitted a report to the emperor, Schmid and d’Asquier tried to get the impression that running the network was of primary importance.50 However, by the 1640s, the system was on the verge of collapse, since there were not enough resources to run it because of the costs of the Thirty Years’ War.

After Schmid’s return from Constantinople in 1643, the task of rebuilding was inherited by his successor, Alexander Greiffenklau (1643–1648). The court was preoccupied at the time with a series of attacks (1644, 1645)51 by the Prince of Transylvania, György Rákóczi I (1630–1648), against the Kingdom of Hungary. These attacks also impeded communication between Vienna and Constantinople. Moreover, the Ottoman war against Venice for the possession of Crete (1645–1669)52 virtually eliminated the possibility of using the Venetian post service, though that passage had been favored by Greiffenklau. Since the resident ambassador was unable to relaunch the “Secret Correspondence,” Hermann Czernin von Chudenitz, the grand ambassador assigned to the Porte in 1644, was charged with the task. However, it seems that this effort was not successful either. Both Czernin and Greiffenklau endeavored to get their letters to Vienna by all possible means, mainly through couriers, embassy secretaries, the Ottoman postal service, and sometimes even through Poland. The temporary disappearance of the “Secret Correspondence” was not necessarily their fault. Indeed, the political situation at the time had a strong impact on communication and determined the options available, namely that diplomats were forced to rely on trusted confidants.53

After the campaigns, the system was revived once again. Greiffenklau was commissioned with the reorganization for the second time. However, despite the efforts of imperial courier Johann Dietz, the reorganization did not succeed because of the war against the Venetians.54 After the resident’s involvement in a political assassination, the situation was further complicated, because it had some diplomatic consequences.55 As for the intelligence, Greiffenklau primarily relied on the Hungarian-born renegade, the grand dragoman of the Sublime Porte (1629–1657), Zülfikâr Ağa.56 The unexpected death of Greiffenklau in 1648 again offered Schmid new opportunities. In 1647, he had already suggested using the services of the German-born renegade interpreter, Hüseyin Çavuş, who went by the pseudonym Hans Caspar and who subsequently became an important spy in the intelligence network of the Habsburg–Ottoman frontier.57

In 1649, Schmid was sent to the Porte as a member of the Aulic War Council to negotiate to extend the peace.58 He introduced there the new resident ambassador, Simon Reniger,59 and he reorganized the “Secret Correspondence.” During Schmid’s diplomatic mission, he recruited competent agents in Buda, Belgrade, and Sofia who were suitable as actors who would forward letters (cf. table), and after some bargaining, he was able to agree on their remuneration.60 In his secret report, he emphasized the importance of regular payments in the future to keep the system running.61 At the same time, he tried to set up the forwarding of letters via Transylvania, which seemed to be the shortest route.62 Communication channels were thus re-established for a while.

In 1650, Johann Rudolf Schmid again (as a baron and grand ambassador) took the ratified document of the peace treaty to Constantinople.63 According to the references, during his embassy, he regularly used the “Secret Correspondence” network, and he tried to replace the lost links (e.g. in Sofia) and provide the actors in the system with adequate payment for the future, thus making Reniger’s work easier.64 In his secret report, he emphasized again that salaries were to be paid regularly to facilitate the rapid flow of information. His suggestions were no doubt inspired by his previous bad experiences.65

From that point on, communication between Vienna and Constantinople seemed relatively stable. The main channels were couriers, correspondence via Transylvania, Ottoman chiauses (çavuş), and the “Secret Correspondence.” Obviously, extraordinary events could cause disruptions. The death of imperial courier Johann Dietz during his mission in the autumn of 1651 led to a serious delay of several months, as all channels were simultaneously interrupted for various reasons.66 However, the increasing number of excursions on the frontier made it essential to get the letters to their destinations as quickly as possible, and usually at least one channel was used to get the information to the right destination. In the autumn of 1652, the death of the letter forwarder of Belgrade (Baggio, recruited by Schmid) caused a further slowdown, and the position in Belgrade remained precarious for the rest of the year.67 According to one of Reniger’s reports to Schmid, between December 1653 and 1654, he sent only one letter out of nine through the “Secret Correspondence” network. This mere fact offers an indication of the seriousness of the problems outlined.68 In 1653, the death of Hungarian palatine Pál Pálffy (1649–1653) caused a disruption on the Transylvanian route, but this was soon resolved diplomatically, although the election of Ferenc Wesselényi as palatine in 1655 caused further interference.69

The main source of information in Constantinople in the early 1650s was Dr. Scogardi, who regularly reported to Schmid,70 and in Buda, mainly during the time of Kara Murad Pasha (1650–1653),71 the German renegade Hans Caspar.72

In the mid-1650s, the “Secret Correspondence” and the whole communi­cation and intelligence network entered a difficult phase. The new pasha of Buda, Sari Kenan (1653–1655),73 took a dim view of the secret transmission of information and assaulted the judge of Óbuda, who was then acting as a letter forwarder. Even the other letter forwarder in Buda, Vuichich/Vuičić (see table), did not dare carry out his duties, and consequently a general atmosphere of fear prevailed in that period.74 Since the sending of letters via Transylvania also seemed uncertain at the time, communication between Reniger and the Viennese court took place via Poland for a few months.75 Finally, the imperial courier Natal de Paulo, also of Ragusan origin, managed to restore the system by filling in the missing links. Furthermore, Hans Caspar found himself in a difficult situation during the time of Sari Kenan, and this was reflected in the low number of reports written by him.76

A completely new situation was brought about by the campaign of Prince of Transylvania György Rákóczi II (1648–1660) against Poland in 1657.77 The channels of communication were entirely changed by the absence of Leopold I (who traveled to Prague and then to Frankfurt), the campaigns, and the move of the Sultan’s court to Adrianople.78 From the available correspondence it seems that the difficulties of “Secret Correspondence” were not fully overcome in 1656, as no suitable persons could be found in Buda or Belgrade. Only the mission of the courier Natal and secretary of the Aulic War Council Peter Franz Hoffmann was crowned with success, and after that, the secret channel of communication was again in operation in 1657.79 Reniger had to follow the Sultan’s court to Adrianople at the end of 1657, and this brought about a dramatic change in the conditions of the channels of communication, because someone else had to be left in Constantinople. However, this topic is beyond the scope of this paper.80 In terms of gathering or passing on intelligence, Hans Caspar was less active than he had been in the early 1650s, and the war had a strong impact on his circumstances and his work as a spy.81

Thus, although the operation of the “Secret Correspondence” was impeded by numerous financial and personal obstacles between 1624 and 1657, efforts were made to restore this important channel of information for Vienna as soon as logistical, financial, and infrastructural circumstances allowed.

Motivation(s), Opportunities, and Risks

If one looks at the members of the system based on the typology outlined above (see table), some conclusions can be drawn about the motivations and risks of being part of the “Secret Correspondence.” As early as the 1630s, the letter forwarders were aware of the importance of their activities and tried to take advantage of them, and they sometimes blackmailed the diplomats.82 Schmid seems initially to have been rather distrustful of the Ragusans, who at that time enjoyed the support of Count Althan, as the case of the so-called “interpreter trial” shows.83 Later, Schmid changed his mind on that matter.

As the letter forwarders were mainly merchants, their main task was to forward letters from both directions (i.e., between Vienna and Constantinople). In their case, therefore, the emphasis was on the task itself rather than the person who executed it. Therefore, letter-forwarding can be regarded as a more easily replaceable function than spying. Their activities were not without risk, however. The sources reveal that in some cases they put their lives at risk. This is also indicated by the fact that Johann Rudolf Puchheim wrote the name of one of the letter forwarders in cipher in his report.84 Greiffenklau in 164585 and, later, Schmid in his 1649 mission pointed out that, due to the Ottoman war against Venice, it seemed difficult to find people among the Ragusans for the task. They were generally on good terms with Venice but were Ottoman vassals as well.86 It was thus necessary to agree on the abovementioned punctual and regular payment.87 A similar example can be found during Schmid’s mission as ambassador when he authorized Baggio, the letter forwarder in Belgrade, to trade in Moravia on behalf of the emperor to ensure the smooth flow of correspondence.88 This means, therefore, that certain letter forwarders had enough bargaining power in matters affecting their own livelihoods, although Baggio could not benefit for long from the opportunity he had won. Nevertheless, even before his death, the Belgrade transporter complained about the lack of payment and obstructed the forwarding of letters.89 The death of the aforementioned courier Dietz illustrates how the loss of a single key person could paralyze the communication system since he was also the one who would have delivered the payment to the letter forwarders. In the mid-1650s, because of the risks, the Ragusan merchant colony in Belgrade forbade their members to participate in the “Secret Correspondence.” This offered Baggio’s successor (Giorgio Cortey) the possibility of bargaining again. In the end, they solved the problem by depositing the letters from Constantinople in a certain house, where Cortey could later pick them up.90 In 1655, the magistrate of Óbuda, who had also been involved in the forwarding of letters, was badly beaten and imprisoned. This was presumably done as a warning to the Ragusans in Buda. That is why the letter forwarder in Buda (Peter Vuichich/Vuičić) decided to move to Belgrade.91 Lazaro, the letter forwarder in Belgrade, was also arrested in 1656, for which he was later compensated by the Habsburg court, as was the magistrate of Óbuda.92

According to the available data (see table), almost all the Balkan letter forwarders were Ragusans, so in their case, there was no ethnic or religious diversity. It was certainly no coincidence that the imperial couriers who recruited Balkan letter forwarders in the 1650s (Natal and Michel de Paulo) were most probably also of Ragusan origin. They were presumably more able to contact the merchants. This also confirms that the Viennese court was aware of the importance of the “Secret Correspondence.”

However, the circumstances of the spies differed from those of the letter forwarders. In their case, not only was the function they played important. The identity of the person himself and his position (e.g., physician) also mattered. Dr. Grassi seemed to be useful for intelligence purposes in Buda (in the 1630s), Constantinople (in the late 1630s), and later the Middle East during the campaign of Murad IV against the Safavids.93 The other doctor, Andrea Scogardi, also reported from both Constantinople and Iaşi.94 In both cases, there is evidence that they provided intelligence not only for the Habsburgs but Ragusa and/or Venice also enlisted their services (Scogardi was also involved in political assassinations), which offers a clear indication of their significance.95 They were also primarily engaged in their profession, so as spies, they were news sources and were not involved in the forwarding of letters. They obviously put themselves at considerable risk by engaging in espionage activities, but as they were doctors, it was quite difficult to replace them, so they did not have to fear strong reprisals. As a group, the spies were more ethnically diverse. Grassi was Ragusan, while Scogardi had been born in Denmark. As for religion, the latter had protestant (Lutheran) roots, but he converted to Catholicism during his studies in Italy.96

The situation of people belonging to the third category was also different from that of ordinary letter forwarders. In their case, the identity of the person in question and his position again played a key role. Matteo Sturani, also of Ragusan origin, was recruited as a letter forwarder in Belgrade in 1624, and he wrote secret reports from Poland in the 1630s.97 After the death of Alexander Greiffenklau, he seemed a potential candidate for the post of resident ambassador, but because of his Ragusan origins and his age, he was eventually dismissed, and Simon Reniger was chosen instead.98 One of the reasons why Simon Reniger was considered more suitable for the post was that, unlike his predecessor, he had followed Schmid’s advice.99 Francesco Vlatchy/Vlatky also reported regularly, but later he proved more unreliable, since he did not receive his regular salary.100 Thus, despite his claims to the contrary, he does not seem to have taken on the risky task out of conviction, but rather for money.

Hans Caspar in Buda was not only useful for espionage, but he also forwarded letters on several occasions. For example, he sometimes copied and forwarded letters to Vienna sent by Reniger, which had been unsealed by the Pasha of Buda. Moreover, he regularly forwarded letters sent by Ottoman chiauses.101 Later, because of the events in Transylvania, Hans Caspar had to leave Buda and those lost access to the infrastructure that had previously enabled him to transmit the information he had acquired. This event proved to be a decisive factor in his later life.102 Nevertheless, Caspar was still seen as a potential spy, as evidenced by diplomatic reports, for example, when he tried to blackmail
Dr. Johann Friedrich Metzger, who had been sent to the camp of the Pasha of Buda (Gürcü Kenan), because the Pasha was ordered to move against György Rákóczi II.103 In this third and last group of the “Secret Correspondence,” therefore, both the functions of the individuals involved and the ethnic composition of the group seem to be mixed, but at the same time, the careers of these people can be traced.

Conclusions

Several important conclusions can be drawn from the present study. First, the Christian vassals facilitated the flow of information between the Habsburg Monarchy and the Ottoman Empire. Ragusa, through its merchants, played an important role in the communication and intelligence system built up by the Habsburgs in the first half of the seventeenth century, known as the “Secret Correspondence.” However, when they had the opportunity, the Habsburgs also used Transylvanian couriers to transmit letters. Second, the functions of acquisition and transmission of information are clearly distinct, so the term “Secret Correspondence” should be understood as referring to the infrastructure itself. Within this system, reports written by spies were also transmitted. Third, it follows that the role of the letter forwarders was merely to transmit information (hence the function itself), and the actual identity of the person who did this was almost immaterial, whereas in the case of the spies, the identity of the individuals in question was a key factor. Fourth, it is also clear from the cases presented that, although the intelligence officers were sometimes able to bargain, the spies and letter forwarder spies were better embedded in the system because of their position and therefore were less likely to rotate. Fifth, the organization of the system shows that the experience gained over the decades was accumulated and put to good use. This is illustrated by the fact that Johann Rudolf Schmid tried to offer Simon Reniger, his successor, the best conditions for the transmission of letters. Thus, Reniger, unlike his predecessor Greiffenklau, regarded Schmid as his master, who introduced him to the mysteries of Habsburg–Ottoman diplomacy. Sixth, personal skills were essential to the organization and operation of the system, as diplomats could use their Italian language skills to liaise with transporters and spies. Likewise, couriers responsible for recruiting new transporters had to rely on their personal talents and language skills to a great extent, too. In sum, talent, professionalism, and a personal network of contacts were key factors in facilitating Habsburg–Ottoman diplomacy in the first half of the seventeenth century.

Table 1. Letter forwarders and Spies in the Service of the Habsburgs between 1624 and 1658

Resident ambassadors in Constantinople	Letter forwarders, their citizenship, and religion)	Letter forwarder spies, the ircitizenship and religion	Spies, the ircitizenship and religion	Citizenship (total)	Religion (total)
Sebastian Lustrier (1623–1629)	Buda Giovanni Pellegrini (1624–1627?), Ragusan, Catholic Tomaso Orosini (Oct 1628–Jan 1629), Ragusan, Catholic	Buda –	Buda Hans Caspar(?), Ottoman Empire, Islam (orig. Catholic)	Ragusa: 2 Ottoman Empire: 1	Catholic: 2(3) Islam: 1
	Belgrade –	Belgrade Matteo Sturani (1624–1626?), Ragusan, Catholic	Belgrade –	Ragusa: 1	Catholic: 1
	Sofia –	Sofia Girolammeo Grassi (1624–?) Mario Cavalcanti (17. Oktober 1628–10. September 1629?), both Ragusan and Catholic	Sofia –	Ragusa: 2	Catholic: 2
Johann Rudolf Schmid (1629–1643)	Buda (from 1634), Ragusan, Catholic	Buda Lupo Lupino (appr. pseudonym), Ragusan, Catholic A noble Turk (appr. Hans Caspar), Ottoman Empire, Islam	Buda –	Ragusa: 2 Ottoman Empire: 1	Catholic: 1 Islam: 1
	Belgrade –	Belgrade Francesco Vlatchy/Vlatky (1628–1632?), Michael Medani (1633?) Both Ragusan and Catholic	Belgrade –	Ragusa: 2	Catholic: 2
	Sofia Stefano Vukovich (Vuković), Ragusan and Catholic	Sofia –	Sofia –	Ragusa: 1	Catholic: 1
	Iaşi –	Iaşi –	Iaşi Dr. Hans Andersen Skovgaard/Andrea Scogardi (1641–1643?), orig. Denmark and Lutheran, later Catholic	Denmark: 1	orig. Lutheran, converted to Catholic faith: 1
	Persia –	Persia –	Persia Dr. Francesco Crasso/Grassi (1637–1638), Ragusan, Catholic	Ragusa: 1	Catholic: 1
	Constantinople –	Constantinople –	Constantinople Dr. Francesco Crasso/Grassi (1640–1642), Ragusan, Catholic Zülfikâr Ağa (1629–1643), Ottoman Empire, Islam	Ragusa: 1 Ottoman Empire: 1	Catholic: 1 unknown
Alexander Greiffenklau (1643–1648)	Buda Peter Vuichich (Vuičić) (ab 1646?), Ragusan, Catholic	Buda –	Buda Hans Caspar, Ottoman Empire, Islam	Ragusa: 1 Ottoman Empire:1	Catholic: 1 Islam: 1
	Belgrade A person who sent some letters back for fear in 1645	Belgrade –	Belgrade –	Ragusa: 1	Catholic(?): 1
	Sofia –	Sofia –	Sofia –	–	–
	Constantinople	Constantinople	Constantinople Dr. Johann Hans Andersen Skovgaard/Giovanni Andrea Scogardi (1644–1645), orig. Denmark and Lutheran, later Catholic Zülfikâr Ağa (1643–1647), Ottoman Empire, Islam	Denmark: 1 Ottoman Empire: 1	orig. Lutheran, converted to Catholic faith: 1 Islam: 1
Simon Reniger (1649–1665) between 1649 and 1658	Buda Peter Vuichich (Vuičić) (1649–1655) Marco Vuichich (Vuičić) appr. brother of Peter (1655) Elias Luschick (Lušič) (1656?), all of them Ragusan and Catholic	Buda Hans Caspar, Judge of Óbuda (János Baán?), Ottoman Empire, unknown	Buda –	Ragusa: 3 Ottoman Empire: 1	Catholic(?): 3 –
	Belgrade Bagio di Simme/Drasili(?) (1649–1653) Giorgio Lamberto di Corti/Cortey/Cortrai (1653–1655) Lazaro Ginreta (1655–1657?), all of them Ragusan and Catholic	Belgrade –	Belgrade –	Ragusa: 3	Catholic: 3
	Sofia unknown	Sofia	Sofia	Ragusa(?): 1	Catholic(?): 1
	Constantinople	Constantinople	Constantinople Dr. Johann Andersen Skovgaard / Giovanni Andrea Scogardi (1653–1656), orig. Denmark and Lutheran, later Catholic Nikusios Panaiotes (Panajoti) (1649–1665), Ottoman Empire, Orthodox Zülfikâr Ağa (1649–1657), Ottoman Empire, Islam	Denmark: 1 Ottoman Empire: 2	orig. Lutheran, converted to Catholic faith: 1 Orthodox: 1 Islam: 1

Archival Sources

ELTE Egyetemi Könyvtár és Levéltár [ELTE University Library and Archives] (ELTE EKL)

G4 (Kuefstain, Acta et epistolae)

Tomus (Tom.) IV, V.

Österreichisches Staatsarchiv (ÖStA)

Haus-, Hof-, und Staatsarchiv (HHStA)

Staatenabteilungen

Türkei I. Kt. 109, 110, 112, 113, 124, 126

Polen I. Kt. 57.

Kriegsarchiv (KA)

Protokolle des Wiener Hofkriegsrates (HKR Prot.) Bd. 304, 313.

Alte Feldakten (AFA) Kt.

Finanz- und Hofkammerarchiv (FHKA)

Hoffinanz Ungarn (HFU) Kt. 339.

Sammlungen und Selekte (SUS)

Alte Postakten (APA) Kt. 6.

Reichsakten (RA) Kt. 302 (Fasz. 185A)

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