International relations in the context of Jocelyne Cesari

A sovereign state is a state that has the highest authority over a territory. It is commonly understood that a sovereign state is independent. When referring to a specific polity, the term "country" may also refer to a constituent country, or a dependent territory.

A sovereign state is required to have a permanent population, defined territory, a government not under another, and the capacity to interact with other sovereign states. In actual practice, recognition or non-recognition by other states plays an important role in determining the status of a country. Unrecognized states often have difficulty engaging in diplomatic relations with other sovereign states.

A territory is an area of land, sea, or space, belonging or connected to a particular country, person, or animal.

In international politics, a territory is usually a geographic area which has not been granted the powers of self-government, i.e. an area that is under the jurisdiction of a sovereign state.

In international relations, power is defined in several different ways. Material definitions of state power emphasize economic and military power. Other definitions of power emphasize the ability to structure and constitute the nature of social relations between actors. Power is an attribute of particular actors in their interactions, as well as a social process that constitutes the social identities and capacities of actors.

International relations scholars use the term polarity to describe the distribution of power in the international system. Unipolarity refers to an international system characterized by one hegemon (e.g. the United States in the post–Cold War era), bipolarity to an order with two great powers or blocs of states (e.g. the Cold War), and multipolarity refers to the presence of three or more great powers. Those states that have significant amounts of power within the international system are referred to as small powers, middle powers, regional powers, great powers, superpowers, or hegemons, although there is no commonly accepted standard for what defines a powerful state.

Political geography is concerned with the study of both the spatially uneven outcomes of political processes and the ways in which political processes are themselves affected by spatial structures. Conventionally, for the purposes of analysis, political geography adopts a three-scale structure with the study of the state at the centre, the study of international relations (or geopolitics) above it, and the study of localities below it. The primary concerns of the subdiscipline can be summarized as the inter-relationships between people, state, and territory.

Geopolitics (from Ancient Greek γῆ gê 'earth, land' and πολιτική politikḗ 'politics') is the study of the effects of Earth's geography on politics and international relations. Geopolitics usually refers to countries and relations between them. According to multiple researchers, the term is currently being used to describe a broad spectrum of concepts, in a general sense used as "a synonym for international political relations", but more specifically "to imply the global structure of such relations"; this usage builds on an "early-twentieth-century term for a pseudoscience of political geography" and other pseudoscientific theories of historical and geographic determinism.

At the level of international relations, geopolitics is a method of studying foreign policy to understand, explain, and predict international political behavior through geographical variables. These include area studies, climate, topography, demography, natural resources, and applied science of the region being evaluated.

In international relations, intergovernmentalism treats states (and national governments in particular) as the primary actors in the integration process. Intergovernmentalist approaches claim to be able to explain both periods of radical change in the European Union because of converging governmental preferences and periods of inertia because of diverging national interests.

Intergovernmentalism is distinguishable from realism and neorealism because it recognized the significance of institutionalisation in international politics and the impact of domestic politics upon governmental preferences.

Arnold Joseph Toynbee CH FBA (/ˈtɔɪnbi/; 14 April 1889 – 22 October 1975) was an English historian, a philosopher of history, an author of numerous books and a research professor of international history at the London School of Economics and King's College London. From 1918 to 1950, Toynbee was considered a leading specialist on international affairs; from 1929 to 1956 he was the Director of Studies at Chatham House, in which position he also produced 34 volumes of the Survey of International Affairs, a "bible" for international specialists in Britain.

He is best known for his 12-volume A Study of History (1934–1961). With his prodigious output of papers, articles, speeches and presentations, and numerous books translated into many languages, Toynbee was widely read and discussed in the 1940s and 1950s.

Diplomacy is the communication by representatives of state, intergovernmental, or non-governmental institutions intended to influence events in the international system.

Diplomacy is the main instrument of foreign policy which represents the broader goals and strategies that guide a state's interactions with the rest of the world. International treaties, agreements, alliances, and other manifestations of international relations are usually the result of diplomatic negotiations and processes. Diplomats may also help shape a state by advising government officials.

An associated state is the minor partner or dependent territory in a formal, free relationship between a political territory (some of them dependent states, most of them fully sovereign) and a major party—usually a larger state.

The details of such free association are contained in United Nations General Assembly Resolution 1541 (XV) Principle VI, a Compact of Free Association or Associated Statehood Act and are specific to the countries involved. In the case of the Cook Islands and Niue, the details of their free association arrangement are contained in several documents, such as their respective constitutions, the 1983 Exchange of Letters between the governments of New Zealand and the Cook Islands, and the 2001 Joint Centenary Declaration. Free associated states can be described as independent or not, but free association is not a qualification of an entity's statehood or status as a subject of international law.

International security is a term which refers to the measures taken by states and international organizations, such as the United Nations, European Union, and others, to ensure mutual survival and safety. These measures include military action and diplomatic agreements such as treaties and conventions. International and national security are invariably linked. International security is national security or state security in the global arena.

By the end of World War II, a new subject of academic study, security studies, focusing on international security emerged. It began as an independent field of study, but was absorbed as a sub-field of international relations. Since it took hold in the 1950s, the study of international security has been at the heart of international relations. It covers areas such as security studies, strategic studies, peace studies, and other areas.

The Westphalian system, also known as Westphalian sovereignty, is a principle in international law that each state has exclusive sovereignty over its territory. The principle developed in Europe after the Peace of Westphalia in 1648, based on the state theory of Jean Bodin and the natural law teachings of Hugo Grotius. It underlies the modern international system of sovereign states and is enshrined in the United Nations Charter, which states that "nothing ... shall authorize the United Nations to intervene in matters which are essentially within the domestic jurisdiction of any state."

According to the principle, every state, no matter how large or small, has an equal right to sovereignty. Political scientists have traced the concept to the eponymous peace treaties that ended the Thirty Years' War (1618–1648) and Eighty Years' War (1568–1648). The principle of non-interference was further developed in the 18th century. The Westphalian system reached its peak in the 19th and 20th centuries, but has faced recent challenges from advocates of humanitarian intervention.

The international community is a term used in geopolitics and international relations to refer to a broad group of people and governments of the world.

The Antarctic Treaty and related agreements, collectively known as the Antarctic Treaty System (ATS), regulate international relations with respect to Antarctica, Earth's only continent without a native human population. It was the first arms control agreement established during the Cold War, designating the continent as a scientific preserve, establishing freedom of scientific investigation, and banning military activity; for the purposes of the treaty system, Antarctica is defined as all the land and ice shelves south of 60°S latitude. Since September 2004, the Antarctic Treaty Secretariat, which implements the treaty system, is headquartered in Buenos Aires, Argentina.

The main treaty was opened for signature on 1 December 1959, and officially entered into force on 23 June 1961. The original signatories were the 12 countries active in Antarctica during the International Geophysical Year (IGY) of 1957–58: Argentina, Australia, Belgium, Chile, France, Japan, New Zealand, Norway, South Africa, the Soviet Union, the United Kingdom, and the United States. These countries had established over 55 Antarctic research stations for the IGY, and the subsequent promulgation of the treaty was seen as a diplomatic expression of the operational and scientific cooperation that had been achieved. As of 2024, the treaty has 58 parties.