This chapter offers an historical grounding in interwar international relations. It tracks and analyses the progress of international relations in the period between World War I (1914–18) and World War II (1939–45), both of which are rightly seen as two major and formative conflicts in international history and indeed for the study of International Relations. It is sometimes assumed that the two World Wars were primarily European affairs, at least in their origins, and reflected the persistence of European predominance in a fast-changing world. Yet these were truly global and globalising wars, as reflected in their causes, courses and consequences, the technologies they employed and the ideas they helped generate. The period in between the wars was a turbulent and unstable one. It foreshadowed European decline and witnessed the rise of the United States, the challenge of the Soviet Union and the Far East and, more gradually, of peoples around the world subject to imperial rule – in short, the interwar period provided the foundations for the international system that developed over the following decades. Many of its contours are still visible today.

This chapter examines the origin of the customary prohibition of the use of force between States and its relationship to article 2(4) of the UN Charter, focusing on the pre-UN Charter era. In doing so, it critically analyses two possibilities for the norm to have emerged prior to 1945: that it developed prior to the UN Charter and article 2(4) was declaratory of that pre-existing custom, or that article 2(4) crystallised a customary rule that was already in the process of formation. It rejects these two possibilities, arguing that article 2(4) was a significant legal development which went beyond the existing laws of the time in order to found a new international legal order in the aftermath of World War II. Any pre-existing customary limitations on the use of force were significantly broadened by article 2(4), and the drafting process was not accompanied by meaningful State practice developing in parallel with this radical change in the law. Therefore, the customary rule prohibiting recourse to force between States must have arisen after the Charter entered into force. The emergence and development of the customary rule from 1945 onwards are examined in the next chapter.

This second historical chapter provides some important episodes in ICRC history between about 1910 (the death of both Dunant and Moynier) and the end of the Cold War (which is when the rest of the book takes off). Thus the chapter introduces the ICRC through a selected review of its history, emphasizing: the development of international humanitarian law and the global Red Cross network, helping to apply that law and Red Cross Fundamental Principles through assistance and protection in the field, and related activities such as protection of political prisoners. All of this sets the stage for a close analysis of the ICRC since the end of the Cold War and particularly since about 2012. If one wants to know if the ICRC is now in demise, one needs a picture of what it was and did in the past.

This chapter discusses Keynes’s Economic Consequences of the Peace as a matrix for understanding the changing institutional landscape of international trade. In 1919, Keynes highlighted the perils of German participation and US non-participation in international politics, twin problems that continued to frame trade debates in the League of Nations for the remainder of the 1920s. Generally, German leaders supported the construction of an open and regulated world economy. Many internationalists were eager to lock Germany into a system of multilateral norms but also feared that integrating Germany into global markets would reinforce its dominance in key strategic sectors. In contrast, the United States remained aloof from League trade negotiations in the 1920s. Europeans were divided over whether to respond with universal trade rules that the United States might eventually be persuaded to follow or with a regionalist approach that would enable Europeans to negotiate directly with their Atlantic neighbour on a more equal footing. As Keynes saw clearly, both sets of concerns were exacerbated by the financial imbalances stemming from war debts and reparations.

I explore the role of identity documents, including forgeries, in this chapter. I analyze the gendered social meanings attributed to passports, as well as the strategies of underage female migrants – the primary targets of the anti-trafficking crusade – in response to state surveillance. Young women were savvy actors in procuring and using forged papers. They stole or borrowed the birth certificates of older sisters, friends, and acquaintances to apply for passports, and they lied, often convincingly, to border control agents about their identity, profession, and final destination. This chapter also shows how the gendered identity of migrants and class-based notions of sexual respectability determined access to the passport, and how age- and gender-based restrictions on mobility prompted some women to resort to forgeries.

Just over a century old, John Maynard Keynes’s The Economic Consequences of the Peace (1919) remains a seminal document of the twentieth century. At the time, the book was a prescient analysis of political events to come. In the decades that followed, this still controversial text became an essential ingredient in the unfolding of history. In this essay, we review the arc of experience since 1919 from the perspective of Keynes’s influence and his changing understanding of economics, politics, and geopolitics. We identify how he, his ideas, and this text became key reference points during times of turbulence as actors sought to manage a range of shocks. Near the end of his life, Keynes would play a central role in planning the world economy’s reconstruction after World War II. We argue that the “global order” that evolved since then, marked by increasingly polarized societies, leaves the community of nations ill prepared to provide key global public goods or to counter critical collective threats.

This chapter attends to the uniquely French stakes of this global moral panic. Early twentieth-century anecdotes attested to the prevalence of French women in brothels overseas, along with the idea that they were the most desirable and best paid in the business. In addition, state-regulated prostitution began in Paris in 1802 and then proliferated across the world. Because most anti-trafficking activists believed that regulationism caused the traffic in women, they considered France a false ally in their crusade. French representatives at international anti-trafficking conventions, and later at the League of Nations, ardently defended state-sponsored prostitution and women’s freedom to migrate for opportunities in the sex industry abroad. They also acknowledged the legitimacy of male demand for prostitution, in stark contrast to Anglo-American anti-vice crusaders. Moreover, by recognizing women’s individual liberty to sell sex, they injected the thorny question of consent into an already contentious discussion. Both proponents and opponents of regulated prostitution battled to determine the terms of the trafficking debate. Respective notions of national character and sexual morality, as well as migration policy, followed along these lines.

This chapter reveals how ideological notions of French decadence, US sexual restraint, and Cuban moral regeneration shaped immigration law and anti-trafficking protocols. Undercover investigations and social scientific studies discovered a flood of European women, especially from France, migrating for work in prostitution. The same studies described the erotic cachet afforded to Frenchness, the global marketing of vice, and what exactly French women offered for sale. According to US and Cuban reformers, a debased European morality promoted these “undesirable” migrations. This premise bolstered exclusionary legislation passed in both countries, barring suspected prostitutes from crossing the border, along with traffickers and pimps. Thus the desire for undesirable women – and not the protection of trafficking victims – motivated immigration reform.

Around the 1880s, the issue of “white slavery” – the ostensibly coerced prostitution of young women – first emerged as a moral problem of international concern. Social reformers, journalists, politicians, and the public debated whether migrant women involved in prostitution had been trafficked, or if they willingly left their homelands for work in the sex trade. I show that trafficking discourse, framed in terms of coercion, passivity, and gendered moral reform, conceals the migration story at the heart of these journeys: most importantly, the search for better paying work, but also the quest for adventure and self-discovery. However, agency and exploitation are not mutually exclusive possibilities. Migrants’ lives unfolded on the spectrum between coercion and choice, and in the interstices of illicit and licit economies. This book seeks to explain why French migrant sexual labor occupied such a prominent place in the underworld of global prostitution, as well as in the imaginaries of anti-trafficking campaigners, immigration officials, and ordinary consumers of vice. It offers a provocative account of France’s role in modern world history: as an exporter of the theory and practice of state-regulated prostitution; of purportedly French sexual practices; and desirable or undesirable French women migrants, depending on point of view.

Chapter 3 traces the historical development of the jus ad bellum from the Peace of Versailles to the adoption of the UN Charter.

This chapter is an overview of central banking developments between 1919 and 1939, highlighting the establishment and operation of 28 new central banks, most in what are now called emerging markets and developing countries. Inspired by expert advice and underpinned by foreign lending, the new banks were designed to function independently from political interference, and to defend the gold standard as part an international, rules-based network of cooperating institutions. The Great Depression revealed the flaws in this setup. As capital flows dried up and international cooperation faltered, the gold standard disintegrated, and central banks were unable to head off macroeconomic and financial collapse. Designed to fight inflation, they were ill-prepared to address financial fragility. In the wake of their failure, a two-pronged reaction set in. Central bank autonomy was curtailed, while monetary policy was subordinated to new policy objectives, including the support of import substitution in Latin America and central planning in Eastern Europe. At the same time, central banks’ powers expanded, as they were transformed into agents of state-led development policy. Thus, the new central banks of the 1920s and 1930s were integrally involved not just in post-First World War reconstruction and the Great Depression, but also in the key economic developments of the mid-20th century.

The Bulgarian National Bank (BNB) was restructured repeatedly between 1926 and 1935, but these restructurings were superficial and incoherent, producing contradictory outcomes. The liberal spirit of the initial 1926-8 reforms dissolved with the onset of the Great Depression. Subsequently, the BNB was endowed with new instruments and tasked with carrying out the interventionist policies adopted in the 1930s, thus paving the way for the bank’s eventual role in the communist planned economy. This chapter focuses on the significance of BNB’s state ownership and on the tight economic conditionality attached to 1926 and 1928 loans sponsored by the League of Nations. By contrasting policies followed in Bulgaria and Greece during the Depression, it challenges Eichengreen’s hypothesis that heavy defaulters and countries leaving the gold exchange standard performed better relative to those that sought to maintain their reputations as decent debtors.

The chapter describe the pivotal role of central banks in stabilizing the international system after 1918. It explains how central bankers were drawn into peace-making efforts, although they had no formal role either in the Paris Peace Conference in 1919, or in the League of Nations, the world’s first multipurpose international organization that was set up in the wake of the war. In the 1920s, central banks would play a pivotal role in global governance, aided by the League’s Economic and Financial Organization (EFO), a forerunner of the institutions created at Bretton Woods after the Second World War. The EFO was instrumental in stabilization of central and eastern Europe, helping also to establish new central banks in the region. The chapter concludes by exploring the significance of central bankers’ breach with the EFO after 1928, the creation of the Bank of International Settlements, and the legacy of these developments for global order in the second half of the 20th century.

Established at the behest of the League of Nations to help the country secure an new international loan, the Bank of Greece was regarded with a mixture of suspicion and hostility from its very foundation. The onset of the Great Depression tested its commitment to defending the exchange rate against domestic pressure to reflate the economy. Its policy response has been criticized as being ineffectual and even detrimental: the bank is said to have been unduly orthodox and restrictive, not only during but also after the country’s eventual exit from the gold exchange standard. This chapter combines qualitative and quantitative sources to revisit the Bank of Greece’s decisions during the Great Depression. It argues that monetary policy was neither as ineffective nor as restrictive as its critics suggest, thanks to a continued trickle of foreign lending but also to the Bank’s own decision to sterilize foreign exchange outflows. It reappraises Greece’s attempt to maintain the gold standard after sterling’s devaluation, a decision routinely denounced as a policy mistake. Finally, it challenges the notion that Greece constitutes an exception to the rule that countries that shed their ‘golden fetters’ faster recovered earlier.

This chapter challenges the conventional chronology of the interwar era that distinguishes the conservative 1920s, when policy makers were preoccupied with the restoration of the pre-First World War liberal economic order, and the revolutionary 1930s, when they reacted to the global economic and financial crisis by pursuing isolationism, state interventionism, and trade blocs. Taking the example of Hungary’s monetary management in the 1920s, it shows that there was more continuity between the two decades than is usually recognized. Due to the dislocations arising in the wake of the war and subsequent peace arrangements, the fragmentation of empires into small ethnonationalist states, and revolutionary and counterrevolutionary political and social upheavals, institutional and policy adjustments in the direction of what was to become mainstream in the 1930s were already budding in the 1920s. The chapter provides empirical evidence of this sneaking nationalization in Hungary’s monetary management, manifest in a combination of adherence to the rules of the gold standard game, on the one hand, and capital-flow neutralization, on the other, depending on what was appropriate to stimulate or sustain domestic economic activity.

This chapter shows how the crisis of the early 1920s and the intellectual relief that followed were essential to shaping European discourses about intellectuals and their roles in democratic societies. It begins by exploring well-known inter-war polemics by Julien Benda, Karl Mannheim, and Antonio Gramsci against the social backdrop of intellectual crisis and reconstruction. The chapter centres on Geneva as a crucible for bureaucracy and home to bodies that sought to categorize and organize international intellectual life. The chapter shows how a wide range of national and international organizations emerged in the 1920s to codify and protect the status of intellectuals and intellectual workers, and argues that all of this activity was motivated and conditioned by the post-war humanitarian crisis. While, by the late 1920s, the rights of intellectuals were increasingly – but unevenly – protected by international legislation, the rise of totalitarianism showed the vulnerability of intellectuals.

Peace planning intensified starting in 1917, as the Russian Revolution and Wilson’s decision to join the war raised its ideological stakes. There were several competing projects for cooperative control over raw materials and for international free trade, but these plans were undermined by conflicts over resource sovereignty and imperial preference. The final League Covenant included a barebones commitment to ‘equitable treatment of foreign commerce’ In the 1920s, Llewellyn Smith, Harms, Coquet, and Riedl used this legal placeholder to revisit the work that was left undone at the peace conference, drawing on the new organizational structures that developed around foreign trade policy during and after the war.

After Llewellyn Smith initially set the League Economic Committee on a cautious course, Franco-German conflict helped stimulate the development of a more ambitious trade agenda that found expression in the League’s 1927 World Economic Conference. Bernhard Harms participated by demanding a more broadly institutionalized international economic regime that would include the United States and would cover sensitive issues skirted by Llewellyn Smith, including reparations, raw materials, and colonial markets. Harms had a prominent bully pulpit from which to promote this vision, as the director of the IfW. He used his position to facilitate ongoing policy dialogue among a large community of League collaborators and critics. He helped establish a novel think-tank environment that spanned business, academia, and government and became an important base of support for the League. In recognition of his pivotal role in international information networks, Harms was asked to coordinate a massive economic bibliography for the League at the end of the 1920s, with backing from US philanthropic societies. This abortive project revealed the limits of Harms’s strategy of transatlantic outreach.