International law in Europe, 700–1200

By Jenny Benham

Was there international law in the Middle Ages? Using treaties as its main source, this book examines the extent to which such a system of rules was known and followed in the period 700 to 1200. It considers how consistently international legal rules were obeyed, whether there was a reliance on justification of action and whether the system had the capacity to resolve disputed questions of fact and law. The book further sheds light on issues such as compliance, enforcement, deterrence, authority and jurisdiction, challenging traditional ideas over their role and function in the history of international law.

International law in Europe, 700–1200 will appeal to students and scholars of medieval Europe, international law and its history, as well as those with a more general interest in warfare, diplomacy and international relations.

• Language: English
• Publisher: Manchester University Press
• Release date: Feb 15, 2022
• ISBN: 9781526142306

Jenny Benham

J. E. M. Benham is Project Officer for Early English Laws at the Institute of Historical Research, London.

Book preview

International law in Europe, 700–1200

artes liberales

Series Editors

Carrie E. Beneš, T. J. H. McCarthy,

Stephen Mossman, and Jochen Schenk

Artes Liberales aims to promote the study of the Middle Ages – broadly defined in geography and chronology – from a perspective that transcends modern disciplinary divisions. It seeks to publish scholarship of the highest quality that is interdisciplinary in topic or approach, integrating elements such as history, art history, musicology, literature, religion, political thought, philosophy, and science. The series particularly seeks to support research based on the study of original manuscripts and archival sources, and to provide a recognised venue for increased exposure for scholars at all career stages around the world.

Previously published

Writing the Welsh borderlands in Anglo-Saxon England

Lindy Brady

Justice and mercy: Moral theology and the exercise of law in twelfth-century England

Philippa Byrne

Rethinking Norman Italy: Studies in honour of Graham A. Loud

Joanna H. Drell and Paul Oldfield (eds)

Emotional monasticism: Affective piety in the eleventh-century monastery of John of Fécamp

Lauren Mancia

International law in Europe, 700–1200

Jenny Benham

MANCHESTER UNIVERSITY PRESS

Copyright © Jenny Benham 2022

The right of Jenny Benham to be identified as the author of this work has been asserted by them in accordance with the Copyright, Designs and Patents Act 1988.

Published by Manchester University Press

Oxford Road, Manchester M13 9PL

www.manchesteruniversitypress.co.uk

British Library Cataloguing-in-Publication Data

A catalogue record for this book is available from the British Library

ISBN 978 1 5261 4228 3 hardback

First published 2022

The publisher has no responsibility for the persistence or accuracy of URLs for any external or third-party internet websites referred to in this book, and does not guarantee that any content on such websites is, or will remain, accurate or appropriate.

Cover image: Federico Zuccaro, The Submission of the Emperor Frederick Barbarossa to Pope Alexander III, c. 1585. The J. Paul Getty Museum, Los Angeles.

Typeset by Newgen Publishing UK

Till min mor,

Ewa Johansson

Contents

Acknowledgements

List of abbreviations

Maps of medieval Europe

Introduction

1The sources of international law: treaties

2That which is practised on a daily basis: displacement of people

3The rules consistently obeyed: redress, amnesty, and transitional justice

4Justifying action: law, responsibility, and deterrence

5Resolving disputes: arbitration, mediation, and third-party intervention

Conclusion

Appendix: List of treaties

Bibliography

Index

Acknowledgements

This book has been long in the making. It was while I was working on the Early English Laws project with Jane Winters and Bruce O’Brien at the Institute of Historical Research that I first started to seriously consider what international law in the medieval period might have entailed. Partly, it was a reaction to the categorisation of a number of pre-1066 English treaties as laws, while those originating in the twelfth century were suddenly termed treaties despite there being no obvious explanation for this, and despite those treaties containing similar legal clauses to the earlier ones. An opportunity to explore this more closely came in 2011 for the project’s final conference in Copenhagen. I was subsequently encouraged to publish that paper as ‘Law or Treaty? Defining the Edge of Legal Studies in the Early and High Medieval Periods’, in Historical Research in 2013, and through that a commitment to write a book on international law was born.

Writing this book, I have racked up a mass of professional and personal debts, most of which I can never satisfy by mere brief mentions here. The greatest professional debt should be paid to Matthew McHaffie, without whose comments and suggestions on several chapters, and many conversations about all things medieval legal history, this would have been a very different book. The following were also kind enough to read and comment on various chapters or aspects of chapters: Hermann Kamp, Jón Viðar Sigurðsson, Rachel Herrmann, Jamie Smith, Ben Morris, and Stephanie Ward. Many kindly provided materials or made suggestions of readings, including Adam Kosto, Bjørn Poulsen, Björn Weiler, Charles West, Dominik Waßenhoven, Fredrik Rosén, Geoffrey Koziol, Gerd Althoff, Hans Jacob Orning, Harald Siems, Helen Nicholson, James Ryan, Kenneth Duggan, Levi Roach, Matt Raven, Paul Webster, Randall Lesaffer, Scott Chaussée, and Yvonne Friedmann. The support, encouragement, knowledge, and scholarly generosity of my colleagues within the Voices of Law international network – Carole Hough, Paul Russell, John Hines, Sara Pons-Sanz, Helle Vogt, and Han Nijdam – has been invaluable too. A special thank you goes to Bill Aird, for the invitation to Edinburgh to discuss the chapter on legal redress; and to Jens Meierhenrich and Campbell Craig for the invitations to attend and contribute to the workshops on transitional justice, and history and political theory. I would also like to thank Isabella Lazzarini for the opportunity to come to Toronto to discuss treaties, law, and diplomacy with the rest of her diplomacy network: John Watkins, Diego Pirillo, Luciano Piffanelli, Timothy Hampton, Randall Lesaffer, Brian Sandberg, Mohamed Ouerfelli, and Bram de Ridder. I learnt a lot!

In addition, I want to acknowledge my considerable debt to my former students Naomi Maher and Eleanor Collingwood, who helped to gather materials for my database on treaties and ‘unemendable’ crimes. So many other students have provided me with opportunities to discuss medieval treaties; Jamie Smith, Ben Morris, Thomas Tollefsen, and Eleanor Stinson in particular, but any student who has taken my Year 2 module ‘War, Peace and Diplomacy’ at Cardiff since 2013 has contributed to the thought process of many aspects of this book. More generally, my colleagues in the History department should be thanked for their continued collegiality and support. Finally, I want to thank the anonymous readers for their incisive comments and suggestions, the copy editor Victoria Chow, Rebecca Wilford of Newgen Publishing, and the team at Manchester University Press – Alun Richards, Jen Mellor, and especially the ever-patient Meredith Carroll.

I gratefully acknowledge the generous financial support I have received from the Leverhulme Trust (for the international network ‘Voices of Law: Language, Text and Practice’); the Centre of Advanced Studies (facilitating my stay in Oslo during 2017–18); and the College of Arts, Humanities and Social Sciences at Cardiff University.

Among my personal debts, those who have frequently provided tea, cake, friendship, and football chat: Ann Shopland, Emily Archer, Lesley Farthing, Tracey Loughran, Federica Ferlanti, Mary Heimann, and Danny Pucknell. For providing my home away from home with so much care: Alan Lane and Gill Boden. To Ellinor and Malene, for continuous sisterly support and indulging my love of ‘piles of stones’. Last, to Keiran and especially to Mel, for always showing that a life of laughter, crazy antics, and good food is ‘where it’s at’!

This book is dedicated to my mother who sadly passed away in the early stages of researching this book. She was the master of boardgames, always up for some foraging adventure in the northern wilderness – I still recall like it was yesterday climbing that 3m fence to reach the mire with cloudberries and the bear lurking in the background – and yet, she always encouraged my thirst for knowledge and books. She instilled in me to never give up, to take risks, to dare to challenge, and to problem-solve at a practical level. In writing this book, I like to think I have used all of these, and so it is right that the dedication of it belongs to her.

Norwich, October 2020

Abbreviations

Maps of medieval Europe

Introduction

It is the contention of this book that there was a notion of international law in the period c. 700–1200. While it is true that there was nothing that contemporaries referred to as ‘international law’ in this period nor were there any physical international institutions along the lines of the United Nations or the International Criminal Court, I argue, nonetheless, that 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. As there were no nation states in medieval Europe but there were still diplomacy and interactions between different communities, it is important that traditional views of state-centred international law and institutions give way to a different paradigm, which recognises the plurality of law and that the locus of political and legal power in the Middle Ages was multi-layered.¹ Recognising this legal plurality allows us to understand how conflict resolution operated within different contexts – cultural, economic, legal, political, and social – and how this translated into what we might think of as international law.

This move would mirror where the field of modern international law is going in the twenty-first century following the increasing challenges of globalisation and terrorism over the past thirty years and the move away from a Euro-centric view of international law.² Indeed, how people resolved conflict at a time when wars and violence may have been more pervasive both between and within polities than today and in a period before fully-fledged nation states, international institutions, and law, has acquired timely relevance in an age of asymmetrical warfare, tensions over natural resources, unilateralism, and ‘ad hocery’; an age in which the world is multi-polar but at the same becoming more polarised; and an age of international protection of individual rights but also protection of the global environment in which those individuals live.³ These trends have resulted in lessening the importance of the nation state as a dominant factor in war and in securing peace, and in the proliferation of non-state actors involved in both conflict and conflict resolution. Conflicts now are frequently not between states but rather expand across states thereby blurring the lines between wars and civil wars. Violence has become harder to categorise into that carried out during war or peace, or between that which is political or criminal.⁴ In short, there are many analogies in the contexts of war and conflict resolution between the medieval and modern periods, and this has also resulted in a resurgent interest in the history of international law.⁵

In this context then, it is important that scholars cease thinking of international law in the very narrow way of it being a law between nations or nation states as it was perceived in the nineteenth or twentieth centuries. As argued by Hathaway and Shapiro, ‘Modern State Conception is both an excessively narrow and historically incomplete account of law. Legal systems can and have existed despite lacking the capacities of a modern state.’⁶ According to Jörg Fisch, ‘International law is, and always has been, law between States and thus between political entities, not law between nations, peoples, or other groups of human beings’.⁷ This is despite the fact that ‘in European languages, the terms for international law used today do not refer to the State but to concepts with different backgrounds: to nations, from which international law, droit international, etc. comes, or to peoples (gentes), from which droit des gens, derecho de gentes, diritto delle genti, Völkerrecht, etc. are derived’.⁸ Evidently, the crucial issue in all of this is what a ‘state’ is – an issue hotly debated among scholars of many historical periods and disciplines. This study follows a similar approach as that proposed by Randall Lesaffer, that international law ‘as a historical concept should be defined as the law regulating relations between political entities that do not recognise a higher authority’, or what Heinhard Steiger has referred to as ‘the law between political powers’.⁹

Despite the renewed interest in medieval international law, the debate on the history of international law in the Middle Ages has rarely moved beyond the contribution of canon law and even the best treatments of the topic tend to leave a gap from the end of the western Roman empire to the revival of Roman and natural law in the twelfth and thirteenth centuries – nearly 800 years. A few examples will suffice to demonstrate.¹⁰ Without dedicating a sentence to developments in the earlier Middle Ages, Stephen Neff declared in his 2014 monograph ‘What medieval Europe did not have was a conception of international law in our modern sense, as a law applying specifically to relations between independent sovereign states’. Medieval people, he argues ‘envisaged a world in which the rule of law made no concessions to even the mightiest of monarchs – and in which those monarchs were accorded no privileged position in drafting the laws. Emperors and kings could no more alter the strictures of natural law than the fabled King Canute could command the tide to recede.’¹¹ The revised version of Wilhelm G. Grewe’s The Epochs of International Law did better; covering the period c. 500–1200 across nearly seven pages, but using these mainly to describe the order of political and spiritual authority (emperor and pope), and the conflict between them.¹² More successfully, the Oxford Handbook of the History of International Law, published in 2012, and Randall Lesaffer’s edited collection, Peace Treaties and International Law in European History (2004), are characterised by a range of strong chapters on different aspects of historical developments, yet most of these seem to start in the later Middle Ages or leave a gap for the period c. 500–1200.¹³ Bruno Paradisi’s collections of essays on the history of international law in the Middle Ages likewise have done much to examine the doctrine and legal institutions of the Middle Ages, even though, again, much of it is focused either on the later period or in tracing the transformation from antiquity to the early medieval.¹⁴ The point about the gap in the scholarly literature is borne out well in Rasilla Del Moral’s overview of international law for the Oxford bibliographies series, which for the period 400 to 1000 lists only a single scholarly work; that of Heinhard Steiger covering the Carolingian period.¹⁵ This gap does not necessarily mean that there was no equivalent of international law in the early Middle Ages, but rather that there seems to have been no systematic reflection on it. While Augustine’s The City of God is the classic work on the idea of the international community, and Isidore’s Etymologiae contains a definition of the ius gentium based on natural law, no early medieval writer in Europe attempted to systemise relations between rulers or how they were regulated.¹⁶ This is in contrast to the Islamic world, where Muhammad al-Shaybānī produced a compilation and systemisation of the rules of Islamic international law under a specialised subject area of Islamic law termed al-Siyar, which covers the laws of war and peace according to the Shari’ah.¹⁷ In other words, scholars interested in the history of international law in medieval Europe have found few sources with which to investigate it, prior to the renewed interest in natural and Roman law in the twelfth and thirteenth centuries.¹⁸

International law is more than doctrine, however, and scholars frequently accept that it has developed in practice over a long time.¹⁹ Yet, works examining international legal practice across any historical period are significantly fewer than those exploring doctrine. The most obvious explanation for this discrepancy, Lesaffer explains as being that the abundance of source material for legal practice makes such studies huge undertakings.²⁰ Heinhard Steiger’s 2010 monograph Die Ordnung der Welt (The Order of the World), with the subtitle Eine Völkerrechtsgeschichte des karolingischen Zeitalters (A History of International Law in the Carolingian Period), is the most successful work to investigate some of these customary practices and their legal context for the earlier medieval period. To avoid anachronistic terminology, he examines specific terms, some of which have a direct link to Roman international law, including ius (law), regnum (realm), territorium (territory), foedus (treaty), pax (peace), societas (community), and deditio (surrender), using these to demonstrate the hierarchical or reciprocal relationships between different powers (‘Zwischen-Mächte-Verbindungen’).²¹ The study’s overarching aim is to investigate the link between legal order and political order, and much of the evidence on specific diplomatic encounters and agreements is analysed with the main purpose of understanding how the two sides conceptualised their relationship with one another into an ordered world. Steiger traces the continuities and discontinuities with international law as it was perceived in the late Roman empire and through the writings of Augustine, and further compares and contrasts this to modern international law. This analytical framework explains his choice of dates for the study: 741–840. That is, the period which he characterises as showing the rapid expansion of the Frankish kingdom into a Carolingian empire through the coronation of Charlemagne in 800, and which ends with the death of Emperor Louis the Pious, Charlemagne’s son, since it was followed by a period of divisions and the eventual demise of the empire created.²² Steiger emphasises the importance of religion for the unity of this empire, which created a common Christian normativity – and a common language in Latin – within which the various ‘powers’ thought and acted.²³ From this, he concludes that during this time of Carolingian dominance, people were generally convinced that there was a common legal-normative order into which they were integrated and that regulated their relationships with one another. He recognises the difficulty of identifying common standards and instead refers to parallel norms of individual legal systems, e.g., for the protection of ambassadors or the taking of oaths, which Steiger highlights corresponds to the concept of ius gentium, the norms that apply to all peoples.²⁴

Steiger’s immense study, covering some 800 pages, is detailed and important; his conclusions have been developed over a lifetime of research as a scholar of the history of international law. While the overall argument about the presence of recognised rules that we can think of as international law is well-made, nevertheless, some of its details are less convincing. For instance, the argument that relations with non-Christian powers were fundamentally different from those with Christian powers cannot be sustained based on the evidence of diplomatic practices. Similarly, the point that the year 751 – the change from the Merovingian to the Carolingian dynasty – was a watershed in the practice of foreign relations is made without much supporting evidence or consideration of the historiography.²⁵ Many of the problems with Steiger’s argument arise from his self-imposed limitations of focusing on the Carolingian realm(s) 741–840. His methodology of examining specific terms and phrases could, as an example, have been significantly enhanced if he had extended the chronology to include the whole of the ninth century. It would also have avoided conclusions such as that it is not possible to determine if contemporaries perceived of methods for the peaceful settlement of disputes arising from treaties, when the flurry of treaties from subsequent decades demonstrates this amply, and not in a way to suggest this was a new practice. Moreover, Steiger’s notion of the Carolingian whole, for all its claim to plurality, and the focus on specific terminology, have led to a lack of sensitivity to nuances between theory and practice in the sources. Furthermore, in focusing on the idea of the Christian empire as the basis of international law – based on Augustine’s City of God – Steiger followed a long tradition of the connection between legal and political theory, so that, ultimately, his study is still closer to the idea of international law than to the practice.²⁶ This present study aims to take Steiger’s work on international law in early medieval Europe one step further by expanding its chronological and geographical focus, but also by diverging from the scholarly focus on doctrine to explore a different type of evidence: treaties. Indeed, treaties and customs (or legal practice) – two of the most important sources of international law – have never received a full scholarly treatment for the period c. 500–c. 1500. Hence, many assertions about international law in the medieval period are currently not based on an examination of the available evidence.

That the treaty is older than the idea of international law seems certain. Indeed, Allott has argued that the ‘practice of treaty-making has continued from the days of the earliest recorded human history to the present day, more or less in isolation from the troubled development of international law in general’.²⁷ In the Middle Ages, as now, the treaty was a central, even fundamental, means of regulating and shaping relations between different political entities.²⁸ 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. It was, in short, the main way in which international law could be consciously created. This study takes as its focus c. 200 written treaties from the period 700 to 1200. The time period has been deliberately chosen to begin before the accession of the Carolingians to the Frankish kingdom in the mid-eighth century – Steiger’s starting point but also the first century from which written treaties have survived from more than a single entity – and to end roughly mid-point between the compilation of Gratian’s Decretum (1130s) and Thomas Aquinas’s Summa Theologiae (1260s) – the most influential works carrying the Roman and natural law traditions, and hence commonly viewed as the starting point for the history of international law in the medieval period. As a corpus of evidence, the number of treaties has certain limitations that should be acknowledged from the outset. As a start, it should be noted that the survival of written treaties is not distributed evenly across every century nor every geographical area in Europe.²⁹ In the ninth and tenth centuries, the majority of treaties originate in the Frankish kingdoms (modern-day France, Germany, and the Benelux countries), the Lombard and later Italian kingdoms, and the Anglo-Saxon kingdoms (modern-day England) (Map 2, 3). Treaties, furthermore, survive in greater numbers from the whole of Europe after 1100, but the real explosion of both treaties and other written evidence comes in the second half of that century. From that period after 1150, we can be very specific about where and from whom the majority of treaties have survived: those involving the English kings Henry II, Richard I, and John; those involving the Emperor Frederick I; and those involving one of the Italian cities (often called city-states) (Map 5). The latter, in fact, are so abundant that it has been necessary to set further limitations.³⁰ Genoa has been chosen as the focus because in its archives survive a large number of treaties with different entities; those of the Latin west and east, as well as Byzantium, and various Muslim powers. The advantage of focusing on Genoa in the twelfth century is hence that its diplomatic relations radiated outwards in all directions, and this sets it apart from other Italian cities, such as Venice, whose relations mainly went eastwards. Moreover, treaties involving the Italian cities are often quite similar, and those from Genoa provide a good representative sample of issues and practices. It is worth noting that even with these particular restrictions, if only a single treaty survives from a certain city, it has more often than not been included, e.g., the 1126 Treaty of Pisa is the sole surviving written treaty of that period involving the city of Amalfi.

A few further comments can be made about the geographical and chronological distribution of surviving treaties. There are no written treaties from most areas inhabited by peoples such as Slavs, e.g., areas known today as Poland and the Baltic States, and only two involving a ruler or other entity from Scandinavia. Similarly, there is only a single written treaty surviving for the whole period involving an Irish ruler, and the first treaty with a Welsh ruler that has come down to us in written form dates to 1201, i.e., outside the chronological scope of this study, but has been included as it is a sole treaty. Moreover, it should be noted that both the eighth century and the eleventh century have a relatively small number of written treaties surviving from the whole of Europe (Map 1, 4). In particular, it is noteworthy that for the reigns of rulers seen by previous scholars as the heyday of the empire doctrine of international law in the period before 1100 – that is, the reigns of Charlemagne (768–814), the three Ottos (936–1002) and Henry III (1039–56) – only five written treaties have survived.³¹ An attempt has been made to draw in, as far as possible, other evidence of international legal practice from those geographical areas or particular centuries. In addition, while this is perceived as a study of international law in Europe, based on the evidence from written treaties, there are some significant exceptions. The first concerns treaties written in Greek or Arabic, which have been excluded due to linguistic limitations. In the small number of cases where a Latin version exists, or where there is a translation in a modern language, a treaty may have been included for comparative purposes. It should be acknowledged, however, that this is not always a satisfactory substitute. The second exception concerns treaties from the Iberian peninsula. Although Latin is known as the lingua franca of medieval Europe, it remains the case that treaties frequently contain terminology specific to a geographical area or to particular political or cultural circumstances. Unfamiliarity with these historical contexts and linguistic limitations in accessing the modern secondary literature, vital for the analysis of both the treaties and the history of the region, has prompted this exclusion. Nevertheless, certain