This Introduction begins by outlining what is meant by international relations. It then tells the story of how and why the academic study of international relations emerged in the early twentieth century before considering the need to ‘globalise’ the study of international relations – to make it an academic discipline more open to non-Western perspectives. It sketches the changing agenda of international relations, a shift that some scholars describe as a transition from international relations to world politics or from the ‘traditional’ to the ‘new’ agenda. Although there is little doubt that, as political reality has changed, new theoretical tools have become necessary to grasp it, we should not assume that the myriad changes in our world have rendered the ‘traditional’ agenda obsolete. As we shall see, the ‘new’ agenda supplements, but does not supplant, the ‘traditional’ agenda. It is now more important than ever to consider the relationships between ‘traditional’ and ‘new’ agendas, and to globalise IR.

For millennia, health and disease have shaped human society in profound and fundamental ways. While events such as the Justinian Plague and ‘Black Death’ decimated the European populations in the sixth and fourteenth centuries respectively, arresting urban development and impacting the relationship between church and state, the introduction of European and African diseases into Latin America is believed to have caused the deaths of up to 90 per cent of some of the continent’s indigenous populations. Biological weapons used during World War I led to international moratoriums on their use, even as more recent ‘naturally occurring’ events extending from the 2003 SARS outbreak, the 2013–16 West African Ebola outbreak and the COVID-19 pandemic have had widespread social, economic and political impacts.

This chapter examines several feminist approaches to the study and practice of international relations. It highlights the similarities between these approaches, but also the differences. It does this first by tracing the interventions made by feminists into international relations and the creation of a distinctly feminist IR agenda. Second, it uses the ‘gender lens’ to demonstrate and analyse how experiences and understandings in international relations can be ‘gendered’. Finally, it explains and examines the critiques made by the different feminist approaches to international relations.

This chapter provides a brief introduction to the ethics and laws of war. The first part outlines what international law and the ‘just war’ tradition say about war; the second explores the conduct of war; and the third examines two recent dilemmas as examples of moral and legal debate: the legitimacy of pre-emptive self-defence and the use of cluster bombs.

The purpose of this chapter is to introduce the contemporary political debates surrounding globalisation. It illustrates the main features of protests against the social consequences of a globalised economy, and it identifies some of the key political issues that scholars and students of International Relations must face when addressing the promotion of justice and effective governance within a more densely connected world.

This chapter introduces the concept and practice of security in international relations. It explores the dilemmas faced by states, individuals and the global community by first looking at contemporary crises and disagreements about security; second, examining how security has been differently defined and focused; and third, surveying how different theoretical approaches have understood and analysed security.

This chapter makes three main arguments. First, ideas and practices of diplomacy have a multi-millennial history – much longer than is generally thought. Second, this long history has been characterised by both continuity and change. As a result, diplomacy has been as much adaptive as resistant to change. And third, that diplomacy is not diminishing in importance. To assess these claims, the chapter first addresses the issue of defining diplomacy, before examining the evolution of diplomacy in terms that may be characterised broadly as pre-modern, modern and postmodern. Finally, the chapter evaluates the relationship between diplomacy and the study of international relations.

This chapter outlines the significance of the digital revolution for International Relations. The first section establishes the political context that shaped the development of the internet, showing how this informed both its technical building blocks and modes of governance. The second section explains how these new technologies also entailed a distinct set of vulnerabilities. In doing so, it highlights the emergence of cybersecurity as an issue of national security, including the potential for cyber warfare between states. The third section introduces the politics of social media platforms that have enhanced pro-democracy movements such as the Arab Spring, but also driven polarisation, fostered extremism and been harnessed by a range of actors, from terrorist groups and intelligence services through to diplomats and even heads of state. The final section tracks the rise of internet sovereignty, which began in the early 2000s and has since become a significant international political tension point. We highlight how some states have sought to control information within their geographical borders, and use online censorship, propaganda and surveillance to govern their populations.

Liberalism is at the heart of modern ‘Western’ history, politics, and international relations. Central to understandings of liberty, freedom, democracy, rights and the rule of law, liberalism has animated debates on abolition and empire, war and peace. This chapter provides an account of liberalism as a contested phenomena that originated at least in the eighteenth century and has had profound international political consequences ever since. To tell this story, the chapter begins by considering how to make sense of the contestations surrounding liberalism, before examining how and why liberalism matters to International Relations at key moments of its development as a discipline: in the age of empires, the inter-war years, during the Cold War and ‘new’ world which ensued, and now in this epoch of endless war.

The Cold War was the most important feature of the international system in the second half of the twentieth century. The rivalry between the Soviet Union and the United States shaped the contours of conflict and cooperation among states and peoples between 1945 and 1991 and its dynamics permeated almost all corners of the globe. Whether in Baghdad, Bangkok or Brussels, the influence of geopolitical and ideological conflict was unmistakable. The Cold War created rivalries and political faultlines that have continued to shape international relations years after its passing. Sino-American competition has become so intense that many think the world is on the brink of another period of bipolar rivalry.

Kabul fell to the Taliban in August 2021 despite peace talk efforts in late 2020 and early 2021. International pundits had been predicting that Ashraf Ghani’s government might need to share power with a resurgent Taliban, but none had expected such a swift and complete takeover as the Americans readied to leave for good. Two decades of international intervention in Afghanistan were erased. The efficacy and desirability of intervention has been thrown into serious doubt, and with it the prospects for post-conflict state-building. This chapter introduces the rise, and possible fall, of the post-conflict state-building agenda. It introduces the reader to important concepts, noting the relationships between state-building, peace-building and nation-building, as well as underscoring the role of liberal ideology in shaping post-conflict state-building efforts, asking readers to reflect on what they believe external actors should, or should not, do.

This chapter suggests paths along which the futures of international relations as subject matter and International Relations as an academic discipline may develop. First, it stresses that the division between the ‘traditional’ and ‘new’ or ‘non-traditional’ agenda is intended as a device to facilitate learning for new students of international relations. Second, it outlines how novel intellectual developments in the field are shaping its future trajectory, with a specific focus on the continued development of a ‘Global IR’; IR’s increasing intellectual engagement with the sociology of Science and Technology Studies (STS) and STEM subjects as sources of conceptual innovation; and recent attempts to define the International as a condition of interactive multiplicity in an effort to clarify its distinctive contribution to the wider social sciences. Finally, the chapter notes that thinking about the future itself is becoming increasingly central to the discipline, with methods of counterfactual analysis, social imaginaries of future histories and utopian idealisations emerging as important theoretical and political projects.

This chapter offers an account of postmodernism. It begins by drawing a distinction between two broad approaches to the postmodern: one that outlines the contours of a new historical period (postmodernity), and another that places emphasis on finding new ways of understanding modern practices of knowledge and politics (postmodernism). The second part of the chapter examines how postmodern ideas entered international relations scholarship, and how ensuing contributions continue to reveal important insights up to the present day. Defining postmodernism is no easy task. Postmodern scholarship is characterised more by diversity than by a common set of beliefs. Add to this that the postmodern has become a very contentious label, which is used less by its advocates and more by polemical critics who fear that embracing postmodern values would throw us into a dangerous nihilist void. But while the contours of the postmodern will always remain elusive and contested, the substantial issues that the respective debates have brought to the fore are important enough to warrant attention.

This chapter introduces students to the rich and controversial legacy of Marxism and one of its major offshoots in the twentieth century, Critical Theory. The chapter is presented in two parts. The first part touches on the historical and intellectual context that ‘created’ Marxism, Marx’s notion of historical materialism and the issue of how Marx’s ideas have been received in IR. The second part concentrates on the two strands of Critical Theory that have emerged within IR: one derived from the so-called Frankfurt School and the other from Italian thinker Antonio Gramsci.

The debate about whether state or non-state players have primacy has been a major preoccupation for International Relations researchers. This chapter argues the key is not so much to determine which players are dominant, but how they interact to produce the prevailing order. The 1985 book Bringing the State Back In declared the return of the state for international politics and political economy (Evans et al. 1985). This chapter argues instead for bringing state–society relations ‘back in’ to the centre of what makes international relations.