International relations

International relations is an academic discipline. In a broader sense, the study of IR, in addition to multilateral relations, concerns all activities among states—such as war, diplomacy, trade, and foreign policy—as well as relations with and among other international actors, such as intergovernmental organizations, international nongovernmental organizations, international legal bodies, and multinational corporations.
International relations is generally classified as a major multidiscipline of political science, along with comparative politics, political methodology, political theory, and public administration. It often draws heavily from other fields, including anthropology, economics, geography, history, law, philosophy, and sociology. There are several schools of thought within IR, of which the most prominent are realism, liberalism, and constructivism.
While international politics has been analyzed since antiquity, it did not become a discrete field until 1919, when it was first offered as an undergraduate major by Aberystwyth University in the United Kingdom. The Second World War and its aftermath provoked greater interest and scholarship in international relations, particularly in North America and Western Europe, where it was shaped considerably by the geostrategic concerns of the Cold War. The collapse of the Soviet Union and the subsequent rise of globalization in the late 20th century have presaged new theories and evaluations of the rapidly changing international system.

Terminology

Depending on the academic institution, international relations or international affairs is either a subdiscipline of political science or a broader multidisciplinary field encompassing global politics, law, economics, or world history. As a subdiscipline of political science, the focus of IR studies lies on the political, diplomatic, and security connections among states, as well as the study of modern international relations within the context of world history. In many academic institutions, studies of IR are thus situated in the department of politics/social sciences. This is, for example, the case in Scandinavia, where international relations are often simply referred to as international politics.
In institutions where international relations refers to the broader multidisciplinary field of global politics, law, economics and history, the subject may be studied across multiple departments, or be situated in its own department, as is the case at for example the London School of Economics. An undergraduate degree in multidisciplinary international relations may lead to a more specialised master's degree of either international politics, economics, or international law.
In the inaugural issue of World Politics, Frederick S. Dunn wrote that IR was about "relations that take place across national boundaries" and "between autonomous political groups in a world system". Dunn wrote that unique elements characterized IR and separated it from other subfields:

international politics is concerned with the special kind of power relationships that exist in a community lacking an overriding authority; international economics deals with trade relations across national boundaries that are complicated by the uncontrolled actions of sovereign states; and international law is law that is based on voluntary acceptance by independent nations.

The terms "International studies" and "global studies" have been used by some to refer to a broader multidisciplinary IR field.

History of international relations

Studies of international relations started thousands of years ago; Barry Buzan and Richard Little considered the interaction of ancient Sumerian city-states, starting in 3,500 BC, as the first fully-fledged international system. Analyses of the foreign policies of sovereign city states have been done in ancient times, as in Thucydides' analysis of the causes of the Peloponnesian War between Athens and Sparta, as well as by Niccolò Machiavelli in The Prince, published in 1532, where he analyzed the foreign policy of the renaissance city state of Florence. The contemporary field of international relations, however, analyzes the connections existing between sovereign nation-states. This makes the establishment of the modern state system the natural starting point of international relations history.
The establishment of modern sovereign states as fundamental political units traces back to the Peace of Westphalia of 1648 in Europe. During the preceding Middle Ages, the European organization of political authority was based on a vaguely hierarchical religious order. Contrary to popular belief, Westphalia still embodied layered systems of sovereignty, especially within the Holy Roman Empire. More than the Peace of Westphalia, the Treaty of Utrecht of 1713 is thought to reflect an emerging norm that sovereigns had no internal equals within a defined territory and no external superiors as the ultimate authority within the territory's sovereign borders. These principles underpin the modern international legal and political order.
The period between roughly 1500 to 1789 saw the rise of independent sovereign states, multilateralism, and the institutionalization of diplomacy and the military. The French Revolution contributed the idea that it was the citizenry of a state, defined as the nation, that was sovereign, rather than a monarch or noble class. A state wherein the nation is sovereign would thence be termed a nation-state, as opposed to a monarchy or a religious state; the term republic increasingly became its synonym. An alternative model of the nation-state was developed in reaction to the French republican concept by the Germans and others, who, instead of giving the citizenry sovereignty, kept the princes and nobility, but defined nation-statehood in ethnic-linguistic terms, establishing the rarely, if ever, fulfilled ideal that all people speaking one language should belong to one state only. The same claim to sovereignty was made for both forms of nation-state. In Europe today, few states conform to either definition of nation-state: many continue to have royal sovereigns, and hardly any are ethnically homogeneous.
The particular European system supposing the sovereign equality of states was exported to the Americas, Africa, and Asia via colonialism and the "standards of civilization". The contemporary international system was finally established through decolonization during the Cold War. However, this is somewhat over-simplified. While the nation-state system is considered "modern", many states have not incorporated the system and are termed "pre-modern". A handful of states have moved beyond insistence on full sovereignty and can be considered "post-modern". The ability of contemporary IR discourse to explain the relations of these different types of states is disputed. "Levels of analysis" is a way of looking at the international system, which includes the individual level, the domestic state as a unit, the international level of transnational and intergovernmental affairs, and the global level.
What is explicitly recognized as international relations theory was not developed until after World War I, and is dealt with in more detail below. IR theory, however, has a long tradition of drawing on the work of other social sciences. The use of capitalizations of the "I" and "R" in international relations aims to distinguish the academic discipline of international relations from the phenomena of international relations. Many cite Sun Tzu's The Art of War, Thucydides' History of the Peloponnesian War, Chanakya's Arthashastra, as the inspiration for realist theory, with Hobbes' Leviathan and Machiavelli's The Prince providing further elaboration.
Similarly, liberalism draws upon the work of Kant and Rousseau, with the work of the former often being cited as the first elaboration of democratic peace theory. Though contemporary human rights is considerably different from the type of rights envisioned under natural law, Francisco de Vitoria, Hugo Grotius, and John Locke offered the first accounts of universal entitlement to certain rights based on common humanity. In the 20th century, in addition to contemporary theories of liberal internationalism, Marxism has been a foundation of international relations.

Emergence as academic discipline

International relations as a distinct field of study began in Britain. IR emerged as a formal academic discipline in 1919 with the founding of the first IR professorship: the Woodrow Wilson Chair at Aberystwyth, University of Wales, held by Alfred Eckhard Zimmern and endowed by David Davies. International politics courses were established at the University of Wisconsin in 1899 by Paul Samuel Reinsch and at Columbia University in 1910. By 1920, there were four universities that taught courses on international organization.
Georgetown University's Walsh School of Foreign Service is the oldest continuously operating school for international affairs in the United States, founded in 1919. In 1927, the London School of Economics' department of international relations was founded at the behest of Nobel Peace Prize winner Philip Noel-Baker: this was the first institute to offer a wide range of degrees in the field. That same year, the Graduate Institute of International and Development Studies, a school dedicated to teaching international affairs, was founded in Geneva, Switzerland. This was rapidly followed by the establishment of IR at universities in the US. The creation of the posts of Montague Burton Professor of International Relations at LSE and at Oxford gave further impetus to the academic study of international relations. Furthermore, the International History department at LSE developed a focus on the history of IR in the early modern, colonial, and Cold War periods.
The first university entirely dedicated to the study of IR was the Graduate Institute of International and Development Studies, which was founded in 1927 to form diplomats associated with the League of Nations. In 1922, Georgetown University graduated its first class of the Master of Science in Foreign Service degree, making it the first international relations graduate program in the United States. This was soon followed by the establishment of the Committee on International Relations at the University of Chicago, where the first research graduate degree was conferred in 1928. The Fletcher School of Law and Diplomacy, a collaboration between Tufts University and Harvard University, opened its doors in 1933 as the first graduate-only school of international affairs in the United States. In 1965, Glendon College and the Norman Paterson School of International Affairs were the first institutions in Canada to offer an undergraduate and a graduate program in international studies and affairs, respectively.
The lines between IR and other political science subfields are sometimes blurred, in particular when it comes to the study of conflict, institutions, political economy, and political behavior. The division between comparative politics and international relations is artificial, as processes within nations shape international processes, and international processes shape processes within states. Some scholars have called for an integration of the fields. Comparative politics does not have similar "isms" as international relations scholarship.