The view of international law as a profession committed to the spread of liberal ideas emerged in Europe and North America in the late nineteenth century.1 One of those ideas was the rule of law. Attempts to realize a global rule of law and attempts to constitute an international community have long been linked. For many international lawyers, this gave international law a sense of forward movement and a clear telos, with the caveat that the reality of unequal power relations meant that international law could never be measured directly against a model borrowed from domestic law and politics.

This chapter explores the political, social, and economic conditions that have shaped the turn to history since the 1990s. Those conditions include the break-up of the Soviet Union and the ‘end of history’ narrative that accompanied a decade of ambitious liberal expansionism, the crisis of liberal internationalism triggered by the war on terror and the financial, energy, food, asylum, and climate crises of the early twenty-first century, and the shift in geopolitics caused by the rise of the BRICS and particularly of China as an economic power. International lawyers in practice and the academy have drawn on past events, practices, records, and cases as argumentative resources in adjudicatory settings and in broader debates over how to understand, justify, or resist the transformation of international law. The turn to history eventually began to be understood as a project that should be distanced from the argumentative practice of international law and measured against the empiricist protocols of academic historians. This chapter returns it to the context of international legal argumentation from which it arose, in order to gain a better understanding of the turn to history as an intervention in present struggles over the meaning of international law.

This concluding chapter argues that the interplay between international law and empiricist history has served to offer a new grounding for formalism in an extremely fraught political context. Historical work is increasingly relied upon as a source of substantive claims about what law really means and of scientific methods for studying the past. Lawyers rely on the scientific tone and resulting truth effects of accounts presented by professional historians to intervene in contemporary debates by using the claims made in those narratives about international law’s ‘true’ origins or ‘real’ history. Appeals to contextualist histories allow lawyers to present their arguments as being grounded on evidence and to characterise the other side in a legal debate as ideologically motivated, presentist, or engaged in myth-making rather than proper scholarship. The chapter argues that international lawyers cannot look to historians (or anyone else for that matter) to save the day with impartial and verifiable evidence-based interpretations of what international law really is, means, or stands for. What then is to be done? The chapter concludes by exploring why and how we might study the international legal past even knowing that writing histories of international law is inevitably a partisan act.

This chapter argues that contemporary claims about what empiricist history can offer international law are part of a longer tradition. A particular vision of law and figure of the lawyer have been central to claims made by empiricist historians of political thought for at least a century. The chapter focuses on four influential scholars whose work has influenced the method debates in international law – Herbert Butterfield, JGO Pocock, Quentin Skinner, and Ian Hunter. It traces the figure of the lawyer as apologist for power that reappears in their texts and against which their historicizing methods are staged. While the figure of the lawyer appears in different guises – as Whig constitutionalist for Butterfield, English common lawyer for Pocock, Italian scholastic lawyer for Skinner, and Prussian natural lawyer for Hunter – in each narrative the lawyer functions as the foil for a new heroic figure. That figure, the historicizing humanist, arrives on the scene to offer an anti-metaphysical challenge to the oppressive authority of received tradition. This chapter situates debates over the turn to method in international law within that longer story, in which historians are able to take up their preordained place as radical disrupters of orthodoxy.

This chapter challenges the representations of international law that dominate the turn to history. The vision of international law as metaphysically grounded and of lawyers as scholastics or moralising judges is resonant because it shores up a familiar fantasy. Yet that vision bears little relation to the ways in which contemporary international lawyers use the past in the practice of making legal arguments. This chapter explores the indeterminacy and capaciousness of the past materials out of which international legal arguments are assembled and the varied roles lawyers are trained to adopt in making such arguments. It shows that international lawyers are already immersed in a centuries-long debate over the grounds of law’s authority, into which historicising techniques and anti-metaphysical approaches have long been incorporated. Many influential forms of international legal thought, including legal realism, positivism, critical legal studies, and game theory, have been informed by an anti-metaphysical orientation. Far from being a revolutionary insight, the claim that historicising a text can settle its meaning is just one of many claims that are already part of the broader argumentative world of international lawyers, and no more likely than any other to resolve interpretative controversies or offer the truth of legal history.

International lawyers are very familiar with the claim that international law has taken a turn to history since the tumultuous decade of the 1990s. As debates over the interpretation of past texts, events, and practices have intensified in the context of a rapidly changing field of international law, history has been presented as offering a silver bullet. While international lawyers are criticised for instrumentalising or mythologising the past in ways that are biased, partisan, and political, professional historical methods are presented as offering an objective, impartial, and evidence-based alternative. This chapter outlines the cross-disciplinary hermeneutic of suspicion that has structured the resulting debates over how the history of international law is understood. It sets out the assumptions underpinning that debate and explores its consequences for the way lawyers and historians represent the nature, functions, potential, role, and limits of international law.

This chapter challenges the claim that historians are able to offer value-free, impartial, and verifiable observations about the history of something called ‘international law’. While numerous historians have criticised international legal scholars for misusing the past to tell stories, draw analogies, or link material from diverse periods, historical work is presented as a process of finding evidence rather than making arguments, committed to reality rather than myths. This chapter argues that histories of international law are necessarily as partisan and political as those produced by the most pragmatic of lawyers. Any study that is described as offering a history of something called ‘international law’, or of a subfield of international law such as international economic law or human rights law, necessarily makes normative and political choices about what international law is and where it is to be found. To show how that works in practice, the chapter explores three empiricist historical accounts that are overtly presented as offering correctives to the distorted, presentist, or incomplete histories of international law produced to date – Lauren Benton and Lisa Ford’s Rage for Order, Samuel Moyn’s The Last Utopia, and Quinn Slobodian’s Globalists.

This chapter relates the turn to history in international law to the corresponding international turn taken in the discipline of history. It explores the effects of translating the stakes of those turns into a technical debate involving abstract claims about the proper scientific methods for understanding the past of international law. The chapter analyses the wide-ranging set of arguments about the scientific nature of empiricist history and the partisan character of international legal arguments that have accompanied the turn to history. It argues that international lawyers have been uncritically receptive of the idea that empiricist historical methods offer a set of technical rules to which legal scholars should conform when writing about the past.