At a time when Brexit, the NI protocol, and the conflict in Ukraine are making most of the headlines, international law – what it is and how it should be enforced or complied with – is never far from discussions in the media. There is a new appreciation among the general public for some of the most important features of international law, as well as awareness about its most spectacular flaws. Today, conflict and its resolution are shaped by international law and attempts to uphold it and to achieve justice for a range of stake holders. That this was the case also in the medieval period, is the subject of my new book International Law in Europe, 700-1200.
The Middle Ages is often characterised as a period in which there was nothing that contemporaries referred to as international law nor were there any physical international institutions along the lines of the United Nations or the International Court of Justice. Nonetheless, there were laws, customs, and institutions that guided interactions between different communities and political entities, protected the rights and status of people and their goods in foreign lands, and acted as deterrents to future conflict. One of the best ways to see this is to examine treaties – one of the main sources of international law even in the modern period. In the Middle Ages, as now, the treaty was a central, even fundamental, means of regulating and shaping relations between different political entities. A treaty between two or more parties could create obligations and responsibilities; outline new or old rights; establish, amend, or suspend customary practice; and devise shared solutions for a range of problems and disputes that faced medieval princes and the societies over which they ruled. Treaties were, in short, the main way in which international law could be consciously created.
International Law in Europe, 700-1200 hence takes a different approach to the subject than most previous treatments of it, deviating from the focus on doctrine and its emphasis on the contribution of canon and Roman law from the twelfth century onwards. Instead, to explore how we can build up a picture of what international law might have been, and how it was understood and practised in a period when no outline of this exists, I have employed a simple framework; namely, that the most lucid argument for the existence of international law is that members of the international community recognise that there exists a body of rules binding upon them as law. Evidence of this belief can be cited in four ways. First, that it is practised on a daily basis. Second, that there is a reliance upon justification of action. Third, that the majority of international legal rules are consistently obeyed. And finally, that it is a function of all legal systems to resolve disputed questions of fact and law. These four categories have provided the basis for the main part of the book.
The four ways of evidencing international law in the period 700 to 1200 demonstrate the challenges faced in ensuring peaceful relations, as well as some of the solutions. To give one example of this; chapter 2, examines the evidence in treaties for displacement of people, which was, and continues to be, one of the most enduring threats to peace and security. Expulsion was both a cause and a result of displacement, and that it was regularly practised throughout the whole period cannot be in doubt. The reasons for expulsion show consistency across time and space – heinous crimes – and dealing with it clearly required a multi-pronged approach involving all levels of society, and both domestic and international institutions at different times in the process: to identify such individuals or groups; to work towards integrating or reintegrating them in the community; or to simply expel them in the first place. The extent to which these measures were successful in meeting the challenge of displacement – like international law as a whole – largely depend on how we balance the various details of the process at specific points in time but also on what we think that international law is and what it should do.
The book highlights the consensual and collaborative nature of international law in the medieval period. Political entities effectively “opted in”, chose to engage and to collaborate as well as comply with treaties and institutions of enforcement – much like international law today. As many recent events and history will tell us, having a large body of law, physical institutions, enforcement methods, and even nuclear deterrence does not create long-lasting or successful peaceful relations with every state or political actor forever. International Law in Europe, 700-1200 shows in various ways that success is about perspective, and that it is important to recognise that there are different ways of perceiving international law – even if they seem unworkable and less successful than our own.
Copies of International Law in Europe, 700-1200 will be available to purchase on the MUP stand at the IMC conference. Alternatively, visit our virtual booth, and use discount code MED22 at the checkout to claim your 40% IMC discount.