The Politics of Reception

400 years ago, Hugo Grotius published his most important work, De iure belli ac pacis (IBP). The work made Grotius famous and earned him the title of father of modern international law. To this day, the work is repeatedly cited as a fundamental text of international law. But what do we actually know about the history of its reception and its politics? A conversation with Edward Jones Corredera and Mark Somos, two of the five editors of The Unseen History of International Law, which addresses these and other questions.

Dear Mark, dear Ed, in 1625, Hugo Grotius first published his De iure belli ac pacis (IBP), which is considered his masterpiece. Together with Matthew Cleary, Pablo Dufour, and Emanuele Salerno, you have just published the book The Unseen History of International Law. In the book, you examine one thousand copies of the first nine editions of IBP published between 1625 and 1650, and even more, annotations left by four centuries of readers. The result is, as the title of your book indicates, a previously unseen history of the reception of IBP. Before we get to your findings, let me first ask: How did you come up with the idea for this mammoth project?

Mark Somos: Thank you very much for this opportunity, Hendrik.

It’s a year of round numbers: I’ve been working on IBP, first published 400 years ago, for 30 years. As a side project, in 2014-2018 I co-authored the global descriptive census bibliography of Andreas Vesalius’ De humani corporis fabrica with Dániel Margócsy and Stephen N. Joffe. That was the third global descriptive census, after Gingerich’s on Copernicus’ De revolutionibus, and the census of Shakespeare’s First Folios by Rasmussen and West. Like in the first two censuses, the annotations and dissemination patterns uncovered by the Fabrica census completely transformed the way we understand not only that specific book, but the entire field that it represents. Unexpected owners, incredibly smart readers’ engagements, family traditions of annotating, strategies to circumvent censorship, and other elements of printing and intellectual history were brought to light.

The next step for me was obvious: I had to propose a census for IBP, so that international law would receive the same radical historical reassessment that cosmology, medicine, and drama had from previous censuses’ systematic excavation of centuries’ worth of annotations; purchasing, binding, co-binding and donation practices; family and institutional traditions; and the dissemination, destruction, and reassembling of copies. I was tremendously lucky that Professor Anne Peters at the Max Planck Institute for Comparative Public Law and International Law (MPIL) agreed to host the project, and the Deutsche Forschungsgemeinschaft (DFG) provided a series of generous grants, for a team of great postdoctorates and myself, for 2019-2025.

Edward Jones Corredera: Thanks for chatting to us, Hendrik.

I would add that Covid-19 had a huge impact on the way we thought about our research. There were so many research trips we had to cancel due to the shutting of borders, particularly at the very outset of the project, and Mark skilfully turned this huge ship around and set us on a better course (e.g. towards the use of online catalogues and the engagement with a broader literature on the subject) while the borders remained shut. In so doing, we had to confront an unexpected challenge: while the internet had opened a huge number of black boxes of knowledge, or at least eased the general access into spaces that were otherwise open to a select crowd, it was also a poor repository for knowledge that some might wish to retain for centuries.

How did you deal with this huge amount of text?

Mark Somos: Regarding the workload and scope, this has indeed been a monumental undertaking. The answer to your question is that for six years we worked hard, we worked together, and in addition to the MPIL staff’s help we also had the support of thousands of librarians, who kindly answered our inquiries and allowed us to inspect copies around the world.

Edward Jones Corredera: The paradox of handling a 400-year-old book that accurately retained partial information while finding that a website built in 2013 was no longer operative due to “link-rot”, and therefore all of the information it once hosted was lost forever – this was a reminder that we need libraries, librarians, and physical copies of knowledge that we wish to preserve for future generations.

It is also worth noting that other scholars might have focused on the production or on the reception of the text: we did both.

This allowed us to find that far from being static, the arguments in IBP changed: IBP was a living and changing text. We discovered that there were close to a thousand changes between the 1625 edition and the 1631 edition and analysed the main themes of these changes; we also found out why in 1642 Grotius used the text’s fame to republish the book and add a new section, which constituted an intervention in a theological debate into which Grotius had been ensnared.

Let’s take a closer look at the content of your book. What results stand out in your analysis of the reception?

Edward Jones Corredera: 1632 saw the publication of a particularly well-curated edition, the Blaeu edition, which became the reference point for many of the book collectors and authors. Our analysis found that the decision to include Mare Liberum in the 1631 and 1632 editions had nothing to do with changes in Grotius’ political thought, as many had previously argued; rather, it was part of a marketing ploy by the Blaeu press designed to outcompete rival printers. After Westphalia, in 1650, the text became a canonical book among European diplomats.

What might surprise readers that assume that Grotius have a type of demiurgic power to create and disseminate their ideas is that printers had a huge influence on the way his texts were read. Printers played an outsized and underappreciated role in the publication of various editions – the study of the rivalry between two printers, Blaeu vs. Janssonius, is an important aspect of our book.

Mark Somos: Ed captured our core findings. A few more that might be worth mentioning are that

(1) censorship and indices of forbidden books did nothing to impair the Catholic reception of IBP (not much discussed in current literature);

(2) IBP may have first appeared on university curricula in Scandinavia in the 1650s, and the first chair of international law was set up for Pufendorf to expound IBP in Heidelberg, as we’ve long known, but IBP was also handed out as prize copies to high school students since the early 1630s, which changes the current account of dissemination completely;

(3) Jesuits were probably teaching IBP all around Europe (they certainly owned an extraordinary number of copies, many of them annotated); and

(4) though 17th-century editions were annotated well into the 20th century, a lot of readers disagreed with IBP from the start, and tried to correct or update elements in their annotations.

If I understand you correctly, you are advocating for a stronger historicization and contextualization of Grotius – essentially arguing against the anachronistic application of his ideas to modern legal contexts. Is that right?

Mark Somos: That is exactly right! After every cataclysm (the demise of the Habsburgs, of Napoleon, multiple Holy Alliances, and two world wars), prominent diplomats of the time decided that the key to reconstructing the international order was to reissue IBP with updated commentaries. Grotius has long been and continues to be widely described as ‘the father of modern international law’, by thousands who have studied, taught, and shaped international law (no word about the mother so far). The ICJ, ITLOS, SCOTUS, domestic courts still cite him whenever they run out of arguments and default to a pious invocation of strategically ambivalent authority. IBP is built into guiding precedents and consequently entrenched in innumerable jurisdictions. ICJ judges wish to endow individuals with standing in international law? Grotius. We need a name for the mystical crystallisation of customary international law? Grotius. How to overcome the Outer Space Treaty’s limitations? Grotius. It’s tragicomic and ought to stop.

Edward Jones Corredera: Indeed, this type of appeal to authority is something that doesn’t fly in philosophy or history and certainly should not fly in law.

There is a profound question here, which Mark has already alluded to, regarding the need of international law for the myth of Grotius. Where does international law derive its legitimacy from? Too often, international lawyers will appeal to Grotius’ authority, and the authority of (a Grotian) tradition, or they will point to the brilliant writings of Grotius. But what happens to the legitimacy of international law if Grotius was just a man, more concerned with theological debates that most lawyers would not understand in 2025, and who despite his fame had to, much to his chagrin, live his life in exile? If Grotius was just a man and not a myth, what will lawyer appeal to then? It is important to be able to answer this question. One might suggest that if the history of international law cannot adapt to changing perceptions in history, then I would say that this reliance on Grotius is no longer a historical one: rather, it means that Grotius has been sublimated into something more akin to the basis for a theological order.

Grotius was himself deeply suspicious of appeals to authority: one should read IBP and study how Grotius challenges the preconceptions of many of his peers when he defends the principle that one man’s right is not diminished by another man’s fear or that free passage to be given to those fleeing from war.

I find this comparison between Grotius as a man and Grotius as a myth highly interesting. And you demonstrate beautifully in your book and in your previous answers that “Grotius” – the myth – has been reinterpreted time and again, with each generation, or perhaps even each author, constructing his or her own Grotius. This social construction of Grotius in the receptions refers to the ongoing debates between lawyers and historians regarding the use of history.

Mark Somos: Our book is basically historians calling lawyers, wanting their Grotius back. Grotius didn’t see anything comparable to the UN, or NATO (which meets at The Hague this month, just before our quatercentennial Hague conference on IBP) – not even the so-called Westphalian order, of course. But Grotius did propose divided sovereignty (he thought hallmarks such as jurisdiction, currency, and territorial rule were alienable to corporations, and federations could be unequal alliances between provinces and the central government) and put free seas at the heart of IBP: features that are starkly alien to current international law. I would also suggest that a bit too many of IBP’s arguments rely on Euripides to be universally applicable today.

Edward Jones Corredera: Indeed, I would argue that too many of his arguments rely on John Chrysostom to be universally applicable today. It is also worth noting that many of the thinkers that lawyers consider to be their own would today be seen as much as philologists and poets as they were lawyers; one cannot simply flatten history and telescope or foreshorten figures from the past to validate a presentist argument. To show that water was a common good Grotius cited Virgil; our erstwhile colleague Francesca Iurlaro brilliantly showed how much of international law turned on poetry.

History is as much about the past as it is about historiography, something which is increasingly out of fashion since it only threatens to undermine claims to innovation and newness. But we should approach the past with the curiosity of Grotius the student, who impressed his elders by reading widely, and not as Grotius the VOC lawyer, a raider of the historical heritage in search for a magical golden dust with which to sprinkle legal arguments. Not all history has a teleological bent.

Let’s take another look at the role of printers, which Ed just mentioned. How did they each construct a new Grotius?

Mark Somos: Our census reviewed the printing history of the first nine editions, from the princeps of 1625 to the 1650 edition, the first one that appeared after the Peace of Westphalia. The nine editions were printed by five publishing houses: the first by Nicolas Buon in Paris, the second (probably) by Andreas Wechel in Frankfurt in 1626, the fourth by Johannes Janssonius in Amsterdam in 1632, the seventh in 1647 by Laurentius, also in Amsterdam, and the others (in 1631, 1632, 1642, 1646 and 1650) by the Blaeu family in Amsterdam.

Three of the nine were pirated and two appeared after Grotius’ death, so Grotius himself played an active role only in four of them. This may not be entirely true: while he was dissatisfied with the authorised first edition, Grotius praised the supposedly pirated 1626 Frankfurt edition, and sent copies to Janssonius long before Janssonius’ own version appeared. Many famous 17th-century works, including Grotius’ Mare liberum and John Selden’s Mare clausum, were commissioned by governments, then suppressed as the political calculus changed, then re-commissioned or “leaked” with plausible deniability. While we have no hard evidence, we do not put it past The Miracle of Holland (as the young Grotius was known) that he covertly lent a hand to some of the alleged piratical editions.

And what were the motives – purely economic, or perhaps also political?

Mark Somos: As far as we can tell, the three pirated versions (Wechel’s 1626 Frankfurt and Janssonius’ 1632 editions, and Laurentius’ 1647 reissue of unused sheets from the 1631 version) were primarily driven by commercial considerations. It’s hard to speculate about Buon’s motives for publishing the very first edition, but Grotius was a well-known author by 1625, and IBP would have been a compelling commercial proposition even if Buon did not foresee the book’s incredible political influence. The first Dutch edition by Willem Blaeu was, we think, partly Blaeu’s job application to become the VOC’s official cartographer, and was partly motivated by Grotius’ political gambit to return home from French exile. Each of the subsequent and widely disseminated Blaeu editions has its own story: the 1632 Blaeu version added Mare liberum in response to Janssonius’ innovative inclusion of the same work in his IBP edition, the 1642 Blaeu IBP added Grotius’ commentary on Paul’s Letter to Philemon, which we believe to have been prompted by a theologico-political debate about obedience and slavery, while the 1646 edition was hailed as the definitive one, since the author died shortly before it appeared and had no further opportunities for revision or expansion.

The silences and gaps in the printing history can also be significant in retracing the constructions of Grotius. Why the decade-long gap between the 1632 and 1642 editions? Why did the printer’s and editors’ apparatus in the 1650 edition make no reference to the Peace of Westphalia? Why did Laurentius think that it was a good idea to reissue the large-format, wide-margin, convenient 1631 edition in 1647: was there a growing demand for copies one could more conveniently study and annotate?

Edward Jones Corredera: Indeed, it is worth considering the difference in the economic outlook of printers and in the writings of Grotius by noting how different the question of monopoly in the 1630s. One might compare the furious battle between Blaeu and Janssonius to corner the market of Grotius’ publications (and later for to achieve a monopoly on the atlas market) and the Dutch jurist’s own use of Aristotle’s tale about Thales, the Greek astronomer. When challenged by a merchant to point out the practical benefits of his scientific endeavours, Thales demonstrated the virtues of his science by using his calculations to predict the weather and anticipate a particularly good season for oil production, renting all the oil presses ahead of time, and thus making a huge profit from sales. Grotius drew on this tale to consider whether this type of monopoly was licit – a moral consideration that did not even feature in the minds of the printers in charge of selling his book. To understand the history of the making of international law we need to take both visions into account.

Among the many annotations you have read, are there any patterns that repeat themselves?

Mark Somos: That is an excellent and difficult question: they are all interesting. Whether readers structured the material through keywords, aides-memoires, numberings, section headings, or by copying scholarly apparatus from later editions into their earlier ones, each of the tens of thousands of annotations we’ve reviewed tells a story. Donation marks, book dealers’ notes, the same reader returning to the copy multiple times during a lifetime, copies being passed down generations or within a legal practice, teachers preparing lecture notes… when we examine the physical copies, the extraordinary legacy of IBP scholarship becomes strikingly vivid, as the books turn into windows on the actual lives of readers over four centuries. There are copies with cat pawprints, young children’s pen trials, pressed flowers, and intimately personal and creative binding choices. The patterns are best seen in the aggregate, and despite the years we have spent exploring them, I’m sure readers will spot things that didn’t occur to us.

Just to give a flavour of the material, there are extraordinary interleaves copies in Copenhagen and Warsaw. The owners bought the loose sheets, put blank sheets on top of every printed sheet, then had the whole thing bound. They are monstrous, huge volumes, in which the readers annotated not only the printed text, but also added exquisitely learned and insightful comments on the blank sheets they’ve inserted. Tantalisingly, we don’t know who these readers were, and whether they were preparing lectures, a new edition, a commentary, and/or a series of court arguments. We urge all Völkerrechtsblog readers to investigate and publish their findings!

I can only second that, Mark! And what stands out in the material: a particularly extravagant, interesting, or funny example?

Mark Somos: So many individual annotations also jump out. Johann Christian Boineburg was a towering scholar and statesman, and his IBP copy has long been admired for his smart annotations. We found several other copies he annotated, one of them in a small US college. Boineburg’s cluster of copies alone, and the annotations he left in them over decades, would and should provide enough raw material for a superb PhD or monograph.

I mentioned how silences, when foregrounded by a comprehensive global census, can become loud. While researching his Copernicus census, Owen Gingerich found stunningly insightful annotations that seem never to have appeared in print. Eventually he figured out who the annotator was, and confirmed that while the annotator taught cosmology and published shorter pieces, he chose never to make his potentially dangerous endorsement of the Copernican system public. In a similar vein, we found the annotations that the great Remigius Faesch, Grotius’ contemporary, professor of law and rector at the University of Basel, left in his IBP copy: tremendously smart and innovative, with no sign of any engagement with IBP in his surviving lecture notes.

Perhaps the most heart-breaking example comes from Heinrich Lammasch, professor of criminal and international law at Innsbruck, member of the Permanent Court of Arbitration, and last Minister-President of Austria. In his 1650 copy, alongside Grotius’ explanation that he had written IBP because some states treat international law as an empty word, Lammasch scribbled, “1914”.

Yes, 1914, shocking indeed. The “scrap of paper” comes to mind, as Bethmann Hollweg is said to have put it. Ed, what stands out for you here?

Edward Jones Corredera: An eerie aspect of many of the copies is that they featured the marks of readers who could have been heavily sanctioned for their ownership of this text, and who wrote sharp commentaries about Grotius’ use of Cicero in the margins with all the care and urgency of a cleric whose career might have been at risk for simply making these notes, and then finding, on the same page, the breezy remarks of a patrician law student who picked up the book decades later, when it was considered a classic textbook they would be expected to know, but which, based on their lack of annotations after the first hundred pages, never finished reading. Some, however, did have to read it from start to finish: in Paris, we encountered the eighteenth-century manuscripts that went into turning IBP into a question-and-answer exam test for future French diplomats at a short-lived diplomatic academy.

Very interesting! More recently, critical and decolonial perspectives on Grotius have also emerged: Scholars such as Martine Julia Van Ittersum have begun to critically examine Grotius’ role as the humanitarian and pacifist founder of modern international law. Does your book provide further impetus to think more deeply about this deconstruction of Grotius?

Mark Somos: The Census is devoted to the printing and reception history of IBP, and addresses larger issues only when the new evidence we uncovered warrants it. However, in an article that in many ways serves as the Census’ companion, we reviewed hundreds of twenty-first-century international law textbooks and their obligatory but cursory, meaningless nod to Grotius as the father of modern international law; as well as ICJ, ITLOS, SCOTUS, and other invocations of IBP as a mind-numbingly unquestioned authority.

What the Census reveals is that Grotius was both a figure of his time, and ahead of his time. His practical legal concerns were widely shared by the first generation of IBP readers, and expanded and developed by subsequent generations. Many annotators engaged with the text critically. Some criticism was retrograde (for instance, berating Grotius for not referring to a narrow denominational interpretation of the Bible enough), while others simply noted that times have moved on, and some of Grotius’ proposed rules were no longer viable due to geopolitical or technological change. That said, many readers also engaged with IBP uncritically, perpetuating its veneration. Those reproductions, reiterations, repetitions are boring. The one clear message from the Census is: don’t be boring, for the sake of posterity at least. You have to be critical to survive and to be remembered.

Edward Jones Corredera: To build on what Mark said, the most interesting readers are those who think with Grotius. The Boston Brahmin and abolitionist Wendell Phillips read the book with great care as he was involved in a number of cases regarding the rights of slaves and freedmen, and one can find in his copy of Grotius a careful cross-reading of the Dutch jurist’s thought about wills and testimonies in one section and fugitive slaves in another. In our book we were able to contextualise these annotations and show how he used Grotius’ writings in some of his cases. Grotius is a great author to think with.

Why is it that anyone has a right to buy but not everyone has a right to sell? Is a king nothing more than a tenant of a state? Did Caligula respect the property of others? What can the study of Druids teach us about arbitration? All of these questions are addressed by Grotius, and the strengths and weaknesses of his answers deserve greater attention.

Indeed, most important and often neglected section of IBP is the one on promises as constituting a basic pillar of law – more lawyers should read that to understand where the strengths, weaknesses, and limitations of law lie, and what modern law owes to older ideas, such as acceptilation.

Looking ahead: What can we learn from the reception history of Grotius for the history of international law, in which great theorists have always been particularly important? Should we perhaps focus more on political practice, as legal historians such as Wolfgang Preiser and Heinhard Steiger have long argued?

Mark Somos: That is an excellent question, but above my paygrade. As an Eastern European who studied in the US and was exposed to the shallow dogmatism of both Marxism-Leninism and Straussianism, I learned to relish minutiae and shun grand theory or generalisations. However, parts of an answer commensurately emerge from the mass of evidence that we’ve uncovered, and they relate to basic cognitive hard-wiring.

Every discipline, scholar, and practitioner needs a starting point and a framework. That is how our brains are built, and we could not function without such frameworks and starting points. As cognitive scientists, behavioural economists, and any observant person knows, it is easy to fall victim to our own necessary biases. It is difficult to keep re-examining our assumptions especially when they are introduced early (such as in the international law textbooks I mentioned) and when there is no obvious need to challenge them in the face of overwhelming, if illusory, consensus. Thus, free seas, the nonsensical IBP-Westphalia nexus, and the relative irrelevance of pre-Grotian and non-Western sources of contemporary international law, become facile and deadly pieties.

This is not to say that all frameworks must perish: as noted, we need them to operate. But any large-scale search through recent international law textbooks, pleadings and actual decisions will show that swathes of the Grotian framework are either irrelevant, or remain relevant for reasons other than the fact that they appeared in IBP. Not only the use of frameworks, but their critical re-examination must be an ongoing and routine task.

This also applies to our own work. The previous three global descriptive census bibliographies are all far from finished: new copies and facts came and continue to come to light after they were published, for instance when privately held copies momentarily resurface at an auction. That is as it should be; no census is every complete. In fact, unlike prior censuses, which tend to fill gaps in data with formulaic phrases, ours takes pride in publishing the occasional blank line, for instance about a copy’s provenance or binding, when we could not get the data required. That is our invitation to readers to fill in the gaps, to use our structure and admittedly partial findings to continue. To paraphrase the old announcement of a succession to the throne: the census is dead; long live the census!

Edward Jones Corredera: This might come as a shock, but there is nothing unique or distinctive about the history of international law. Most other areas of history are riddled with huge historiographical debates about how exactly to study the past – this is what makes the study of history more rigorous and exciting. Today, the field of the history of international law seems to be going through its own teething pains as it figures out how to study the past – but it is doing so in isolation, in an entirely self-referential way, with many of its leading proponents appealing to their authority, and without looking at how other fields of knowledge – the history of economics or politics – dealt with methodological questions of prosopography, the relationship between the Left and the study of empire, and indeed the virtues and vices of social and cultural history. Historians of international law ought to read history beyond histories of international law – only then will we be able to have both sweeping accounts of its origins and granular narratives about its major and minor characters. At the moment, most histories of international law read like anthropological accounts penned by authors who have never read a book written by an anthropologist and authored for bureaucrats with too much time on their hands. In IBP, Grotius himself warned against uncritically following the example of ancient authors: we should not uncritically trust the epistemological basis of our field, let alone that of its founders.