The Correspondence of Johann Christian von Boineburg

Primary Contributors:

Gábor Gángó (University of Padua and Erfurt University)

Detail from Samuel Pufendorf’s letter to Johann Christian von Boineburg of 7/17 February 1663 (Bavarian State Archives Würzburg, Gräflich von Schönborn’sches Archiv, 2946; image © Gábor Gángó)

Johann Christian von Boineburg (1622–1672)

Johann Christian von Boineburg was born in Eisenach on 12 April 1622. He studied in Jena and later in Helmstedt where Georg Calixt (1586–1656) and Hermann Conring (1606–1681) were his teachers. His eminent son, Philipp Wilhelm Reichsgraf von Boineburg (1656–1717), resulted from his marriage to Anna Christine Schütz von Holzhausen. Johann Christian’s last years were shaped intellectually by an encounter with a young lawyer from Leipzig, Gottfried Wilhelm Leibniz, who became not only tutor to Philipp Wilhelm but also, thanks to Boineburg, took up employment at Johann Philipp von Schönborn’s court in Mainz. A number of the young Leibniz’s works were written in some form of collaboration with Boineburg. Boineburg died on 8 December 1672 in Mainz. Philipp Wilhelm was appointed governor of the city of Erfurt under the rule of electoral Mainz and rector of Erfurt University, and he transferred his father’s library from Mainz to Erfurt to conserve and enlarge it.

Boineburg started his political career as a diplomat in the service of Hessen-Darmstadt and Hessen-Kassel. In 1652, he entered the service of the Archbishop and Elector of Mainz, Johann Philipp von Schönborn. As chief minister in the court of Mainz, he participated in the Assembly of the Imperial Estates in Regensburg in 1653 where he converted to Catholicism. This move not only facilitated him a career at a Catholic court but also harmonized with his intellectual inclinations and irenic efforts. Boineburg’s chief achievement as a politician was the forging of the Rhine Alliance in 1658, although his ambition for appointment to the office of the Imperial Vice-Chancellor was not fulfilled. In 1664, Boineburg fell into disgrace with the Elector of Mainz and, although he was released from prison the following year, restoration of his political positions were not forthcoming. Thereafter Boineburg dealt mainly with political counselling in Imperial matters. In 1668–9, the opportunity arose for a new start in European politics as special envoy for the Count Palatine Philipp Wilhelm von Neuburg at the Polish royal election. Boineburg’s considerable efforts in pamphlet writing, correspondence, and negotiations in the interest of the Count Palatine’s election remained unsuccessful, however.

An underexplored fact in Boineburg scholarship is that his intellectual ambitions rivalled those he held in the political sphere. Amongst the ‘most desirable things’ (summe optanda) in life, he mentioned the ‘indefatigable and inexhaustible avidity for knowledge’ (sciendi indefessa et inexhausta aviditas; see a handwritten note in the copy of Abraham Bucholcer’s Index Chronologicus in Boineburg’s library, Erfurt University Library, sign. 03-Hs. 800214.) This intellectual appetite prompted the ‘Maecenas Germaniae’, as contemporaries sometimes referred to him, to assemble an exquisite 10,000-title private library. Riddled with and interlinked by extended reading traces, text-bound commentaries, and independent annotations, Boineburg transformed the volumes of his book collection into a gigantic encyclopaedia, the actual scientific purposes and operational logic of which is yet to be decoded. As another significant achievement in scholarly matters, Boineburg created an extended, international network of correspondents, consisting of permanent, temporary, and occasional contributors to and discussion partners of his various projects, which encompasses, amongst other topics, book acquisition and reviewing, Church history, religious reconciliation, and—above all—a lifelong interest in the person and works of Hugo Grotius. Closest correspondence partners and executors of Boineburg’s various commissions were the physician and Helmstedt university professor Hermann Conring (1606–1681) and the classical philologist and historian from Strasburg University, Johann Heinrich Boeckler (1611–1672). This limitless drive to assemble knowledge and the preferred collective character of scholarly research hindered Boineburg’s productivity as an author. Besides occasional political writings, a great number of plans and drafts, titles and tables of contents, or fragments (at best) survive to assist in the reconstruction of the intellectual portrait of this central figure in the seventeenth-century republic of letters.

Partners and Additional Contributors

Johann Christian von Boineburg’s letters from German libraries and archives (above all, Erfurt University Library, Gießen University Library, Bavarian State Archives Munich, Herzog August Library Wolfenbüttel, State Archives of Lower Saxony Wolfenbüttel, and the Bavarian State Archives Würzburg), were collected by Gábor Gángó whilst on the MWK-COFUND Fellowship of the Max Weber Centre for Advanced Cultural and Social Studies at the Erfurt University (Marie Skłodowska-Curie Grant Agreement No. 665958) from 2016 to 2018. To acquire basic skills in assembling the metadata of early modern scholarly correspondence, Gábor Gángó participated in the 2018 Training School held at Tallinn, Estonia, as part of the European COST Action ‘Reassembling the Republic of Letters‘ and he is grateful to Professor Howard Hotson, Miranda Lewis, and the editorial team at EMLO for their support. The partial processing of the metadata of the letters as well as their hitherto unfinished transcription was made possible by the postdoctoral fellowship of the Erfurt University 2018–19. The completion of the metadata preparation for upload to the EMLO union catalogue is being enabled by a postdoctoral research grant at the University of Padua in 2021–22. The project ‘From Venice and Rome to Mainz: Italian Books from Humanism to Counter-Reformation in the Library of Baron Johann Christian von Boineburg’ is hosted within the collaborative project PRIN ‘Books in Motion: Circulation and Construction of Knowledge between Italy and Europe in the Early Modern Period’ and ‘Mobility & Humanities’. Special thanks are due to Frank GrunertKnud Haakonssen, Bettina Hollstein, Paola Molino, and Martin Mulsow for initiating and/or upholding the Boineburg project.


Key Bibliographic Source(s)

Boecler, Johann Heinrich, Bibliographia Critica, ed. Johann Gottlieb Krause (Leipzig: Grossius, 1715).

Conring, Hermann, Opera, volume 6, ed. and annotated Johann Wilhelm Göbel (Aalen: Scientia Verlag, 1973 [reprint of Brunswick, 1730]).

Elswich, Johann Hermann, ed., Epistolae familiares varii theologici potissimum argumenti (Wittenberg: Samuel Hannaver, 1719).

Gröning, Johann, Bibliotheca juris gentium Europaea, seu de juris naturae & gentium principiis juxta doctrinam Europaeorum libri III (Hamburg: Gottfried Liebezeith, 1703).

Gruber, Johann Daniel, ed., Commercii Epistolici Leibnitiani (Hannover/Göttingen: Schmid, 1745).

Meelführer, Rudolph Martin, Io. Christiani L. Baronis de Boineburg … Epistolae ad Jo. Conradum Dietericum (Nürnberg: Wolfgang Michaelles, 1703).

Pufendorf, Samuel. Briefwechsel, ed. Detlef Döring (Berlin: Akademie Verlag, 1996).

Palladini, Fiammetta, ‘Le due lettere di Pufendorf al barone di Boineburg: quella nota e quella “perduta”’, Nouvelles de la République des Lettres, 1984/1, pp. 119–44.


The number of the surviving letters seems to amount to between three and four thousand. Political correspondence with Philipp Wilhelm von Neuburg, Johann Philipp von Schönborn, and Melchior Friedrich von Schönborn make up some several hundred in total. Boineburg’s Polish political correspondence in 1668–9, as well as his family letters, amount to hundreds respectively. The rest consists of scholarly correspondence, which had the best chance of preservation due to its significance for contemporary and eighteenth-century readers and which resulted in a proliferation of hand-written copies and printed editions. The political and family correspondence is in German, while scholarly letters were written overwhelmingly in Latin.

The list of Boinburg’s erudite correspondents include, amongst many others: August, Herzog von Braunschweig-Lüneburg; Heinrich Julius Blume; Johann Heinrich Boecler; Johann Andreas Bose; Georg Calixt; Hermann Conring; Vitus Erbermann S. J.; Ferdinand Fürstenberg; Robert de Gravel, Abbé; Johann Friedrich Gronovius; Isaac Gruterus; Johann Heinrich Hottinger the elder; Athanasius Kircher; Peter Lambeck; Gottfried Wilhelm Leibniz; Hugues de Lionne; Edmond Mercier; Barthold Nihus; François Ogier; Samuel Pufendorf; Samuel Rachel; Veit Ludwig von Seckendorf; Ezechiel Spanheim; Friedrich Spanheim; Gisbert Voetius; and Erhard Weigel.


Detail of letters from Barthold Nihus to Johann Christian von Boineburg, collated into a volume from Boineburg’s private library (Erfurt University Library, 03-T.pol. 4o 00139; image © Gábor Gángó)


Boineburg—as a politician as well as a scholar—was a prolific correspondent. Of his political correspondence both incoming as well as outgoing letters have survived, including collections of his exchanges with Johann Philipp von Schönborn (Würzburg), Melchior Friedrich von Schönborn (Würzburg), and Philipp Wilhelm von Neuburg (Munich), and as well as the pieces of his correspondence conducted as special envoy to the Warsaw royal election Diet in 1669 (Munich).

From his scholarly correspondence, it is mostly the incoming letters that have survived. His correspondence with Johannes Konrad Dieterich from the 1640s document his admiration of Hugo Grotius (ed. Meelführer, 1703). In the 1650s, his scholarly correspondence (primarily with Hermann Conring) is focused on Reichspublizistik on the one hand and an encyclopaedic project with Grotius in its centre on the other. In connection with this, certain letters deal with the enlargement of his library, and various events in the republic of letters. From 1660 to 1664, a considerable growth may be observed concerning the extensity, as well as the intensity, of his surviving correspondence. Samuel Pufendorf’s Elementa jurisprudentiae universalis (1660) as a rival approach to Hugo Grotius’s work prompted a shift in Boineburg’s interest towards natural jurisprudence. On this footing, he built a network, national and international, to discuss Grotius’s merits in theology, history, and jurisprudence as well as to update his knowledge concerning the collection and edition of Grotius’s works and correspondence. His correspondence with Pufendorf and its reverberations in his network pushed Boineburg into the centre of the early debates on natural law in Germany for a year or two. His political fall in 1664 resulted in an abrupt decline in his correspondence, although it  gained momentum again in the last years of his life during which (apart from his efforts to make Samuel Rachel write a ‘Christian’—i.e., New Testament-based—natural law emulating John Selden’s Jewish natural law) Boineburg was an observer rather than an inspiring force of the proliferating scholarship on natural jurisprudence.

The scholarly correspondence survived mainly in contemporary copies in the Herzog-August-Library Wolfenbüttel. The original pieces of his correspondence with Hermann Conring in the State Archives of Lower Saxony in Wolfenbüttel were destroyed during World War II. These collections provided the base of Johann Martin Gruber’s 1745 edition the aim of which was to keep Boineburg’s memory alive and revive the intellectual context of Leibniz’s years of formation. Some of the originals are preserved among Boineburg’s papers in the Archives of the family von Schönborn as a deposit at the Bavarian State Archives in Würzburg. Correspondence with Johann Heinrich Boecler survived partly in Hamburg and partly in copies at Gießen University Library among the papers of Georg Christoph Joannis who collected materials for a planned biography of Boineburg. Other pieces of his correspondence are scattered through Europe, such as that with Athanasius Kircher in Rome, with Johann Michael Dilherr in Cracow, with Peter Lambeck in Vienna, etc. The inventory of Hermann Conring’s correspondence is available in Ammermann’s 1983 publication. Boineburg’s (and Hermann Conring’s and Johann Heinrich Boecler’s) correspondence can be found in libraries and archives in Germany and Europe as follows (although this list is far from being exhaustive):

Staats- und Universitätsbibliothek Hamburg: Hermann Conring‘s correspondence with Johann Heinrich Boecler and Johannes Andreas Bose (Sign.: 4o45).

Royal Library Copenhagen: Boineburg‘s correspondence (KBK NKS 2330.4°, GKS 2134.4°, Bøll.Brevs.U 4° 127, Bøll.Brevs. U 2° 66, Bøll.Brevs. U 1.

Biblioteka Jagiellońska, Cracow: Boineburg’s correspondence with Johann Michael Dilherr (Sammlung Meusebach, M 87-M 95).

Germanisches Nationalmuseum Nürnberg: Hermann Conring’s letter to Hugo Grotius, s.d., Helmstedt (Sign: V. Aerzte Deutschlands).

Archivio della Pontifica Università Gregoriana, Rome: Boineburg’s correspondence with Athanasius Kircher (Ms 557A, f. 283r, Ms568, f. 118r, 119v, f. 98r-v.

Österreichische Nationalbibliothek, Vienna: Boineburg’s correspondence with Peter Lambeck (ÖNB Cod. 9713, f. 1r, 120r–121v, 166r–v, 291r–v und Cod. 9714, f. 40r–v, 100r–101v, 186r).

Herzog-August-Bibliothek Wolfenbüttel: Scholarly correspondence of Johann Christian von Boineburg, Hermann Conring, and Johann Heinrich Boecler (54 Extrav., 64.45. Extrav., 84.9 Extrav., 84.12 Extrav., 149.3 Extrav., 149.6 Extrav.).

Niedersächsisches Landesarchiv Wolfenbüttel: Correspondence of Johann Christian von Boineburg and Hermann Conring (1 Alt 22 Nr. 198).

Bayerisches Staatsarchiv Würzburg: Gräflich von Schönborn’sches Archiv, v. Boineburg (Boyneburg): correspondence with Melchior Friedrich von Schönborn (1456); correspondence with Heinrich Julius Blume (1842); scholarly correspondence (2900–2973); correspondence with Elector Johann Philipp (3027–3044); political correspondence in chronological order (3068–3270); family correspondence (2371–2375); correspondence with Conrad Breunig, Soc. Jes. (2759).

Bayerisches Staatsarchiv München: political correspondence with Count Palatine Philipp Wilhelm von Neuburg (Kasten blau 60/19 and 60/26).

Bayerisches Staatsarchiv München, Geheimes Hausarchiv: correspondence concerning the Polish royal election 1668-69 (Korrespondenzakten 144/2 and 144/3).

Scope of Catalogue

A full inventory of Johann Christian von Boienburg’s correspondence, even one focussed solely on what survives, is a daunting task. Collation of the metadata will concentrate initially on the publications and archival collections containing the scholarly correspondence. Other batches of letters will be itemized in parallel with work on Boineburg’s intellectual and political biography.

Further resources

Ammermann, Monika, ‘Die gedruckten Briefe Hermann Conrings und die Brieftypologie des 17. Jahrhunderts,‘ in Stolleis, Michael, ed., Hermann Conring (1606–1681): Beitrag zu Leben und Werk (Berlin: Duncker & Humblot, 1983), pp. 437–63.

Arnswaldt, Albrecht, De Vicariatus controversia. Beiträge Hermann Conrings in der Diskussion um die Reichsverfassung des 17. Jahrhunderts (Berlin: Duncker & Humblot, 2004).

Conring, Hermann, Die Bibliotheca Augusta zu Wolfenbüttel: zugleich über Bibliotheken überhaupt. Brief an Johann Christian Freiherrn von Boineburg, tr. and ed. Peter Mortzfeld (Göttingen: Wallstein, 2005).

Paasch, Kathrin, Die Bibliothek des Johann Christian von Boineburg (1622–1672): ein Beitrag zur Bibliotheksgeschichte des Polyhistorismus (Berlin: Logos-Verlag, 2005).

Stolleis, Michael, ed., Hermann Conring (1606–1681): Beitrag zu Leben und Werk (Berlin: Duncker & Humblot, 1983).

Ultsch, Eva, Johann Christian von Boineburg: ein Beitrag zur Geistesgeschichte des 17. Jahrhunderts (Würzburg: Becker, 1936).

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