CSS International Relations: the evolution of international society

This topic asks how today's world of nearly 200 sovereign, legally equal states came about. CSS questions test whether you can trace the story in order, explain the key turning points (Westphalia, Vienna, the League, the UN, decolonisation, the end of the Cold War) and use the English School concept of international society to analyse it.

1. Key concepts

International system (Hedley Bull): a system of states is formed when two or more states have sufficient contact between them, and sufficient impact on one another's decisions, to cause them to behave, at least in some measure, as parts of a whole. International society (Hedley Bull): a society of states exists when a group of states, conscious of certain common interests and common values, form a society in the sense that they conceive themselves to be bound by a common set of rules in their relations with one another, and share in the working of common institutions.

The difference is between interaction and shared rules. States can be in a system (fighting, trading) without being in a society (accepting common rules). Bull added a third idea, world society: shared interests and values linking individuals and peoples across the whole of humanity, not only states.

Adam Watson described a spectrum of state systems from complete independence, through hegemony, suzerainty and dominion, to empire. Most historical systems sat somewhere in the middle; the modern system of formally equal sovereign states is unusual.

2. Ancient state systems

2.1 The ancient Near East

The city-states of Sumer in Mesopotamia (third millennium BC) made treaties, settled border disputes and exchanged envoys. In the 14th century BC the Amarna letters show the great kings of Egypt, Babylon, the Hittites, Mitanni and Assyria addressing one another as "brother", exchanging gifts and marriage partners and sending messengers. This was an early diplomatic society among rough equals, with a clear distinction between great kings and smaller vassal rulers.

2.2 Classical Greece

The Greek poleis (city-states) shared language, religion and festivals such as the Olympic Games, used arbitration and proxenoi (local representatives of another city) and formed leagues. Yet they fought constantly. Thucydides' account of the Peloponnesian War (431 to 404 BC) between Athens and Sparta is still read as a study of power, fear and the balance of power. The Greek system ended under Macedonian and then Roman domination.

2.3 China and India

• China: in the Warring States period (475 to 221 BC) several independent kingdoms competed through war and alliance until the Qin unified China in 221 BC. Later Chinese practice was a hierarchical tributary system, in which neighbours acknowledged the emperor's superiority in return for trade and recognition, the opposite of sovereign equality.
• India: Kautilya's Arthashastra, linked to the Mauryan court (around the 4th century BC), describes the mandala theory: a neighbouring state is a natural enemy and the state beyond it a natural friend. It is an early theory of balance of power and statecraft.

2.4 Rome and the Islamic world

Rome developed the ius gentium (law of peoples) for dealing with foreigners, but in the end it was an empire, not a society of equals. The Islamic caliphates produced a sophisticated law of war and peace, the siyar, most famously set out by the jurist al-Shaybani (8th century). It covered treaties, treatment of envoys, prisoners and non-combatants and safe conduct (aman), and divided the world into dar al-Islam and dar al-harb, with an intermediate category of states bound by treaty. Envoys were protected, an idea shared with nearly every civilisation.

Exam tip: Use the ancient systems to show that the European states system is one example among many, not the only form of international order. This answers the common criticism that the English School is Eurocentric.

3. Medieval Europe

3.1 Respublica Christiana

Medieval Latin Christendom was not a system of sovereign states. Authority was overlapping: the Pope claimed spiritual supremacy, the Holy Roman Emperor claimed a universal secular role, and kings, princes, bishops, free cities and feudal lords held layered rights over land and people. A noble could owe loyalty to several superiors. Ideas of a single Christian community and natural law limited war, at least in theory, through doctrines such as just war (Augustine, Aquinas).

3.2 Towards the modern state

• The Italian city-states of the 15th century (Milan, Venice, Florence, Naples, the Papal States) developed resident ambassadors and practised a deliberate balance of power, as in the Peace of Lodi (1454).
• The Reformation (from 1517) broke the religious unity of Christendom. The Peace of Augsburg (1555) let each German prince choose his territory's religion (cuius regio, eius religio).
• Jean Bodin (1576) defined sovereignty as absolute and perpetual power within a state; Hugo Grotius (On the Law of War and Peace, 1625) argued that states were bound by a law of nations even without a common ruler.

4. The Peace of Westphalia and sovereignty

4.1 The settlement of 1648

The Peace of Westphalia was made up of the treaties of Osnabrück and Münster, signed in 1648. They ended the Thirty Years' War (1618 to 1648) in the Holy Roman Empire and, through a separate Spanish-Dutch treaty at Münster, the Eighty Years' War, recognising Dutch independence. Swiss independence from the Empire was also confirmed.

• German princes gained the right to make alliances and conduct their own foreign policy (provided not against the Emperor).
• The religious settlement of Augsburg was confirmed and extended to Calvinists.
• The Pope's protests were ignored, showing that religious authority no longer governed relations between rulers.

Westphalian sovereignty: the principle that each state has exclusive authority over its own territory and population, and that outside actors have no right to interfere in its domestic affairs. It implies the legal equality of states and non-intervention.

4.2 The "Westphalian myth" debate

Many scholars (for example Andreas Osiander and Stephen Krasner) argue that 1648 did not create sovereign equality: the treaties preserved the Holy Roman Empire and gave France and Sweden rights to guarantee its constitution, which is a form of intervention. Krasner calls sovereignty "organised hypocrisy" because powerful states regularly violate it. The modern view is that Westphalia was a milestone in a long process, not a single founding moment.

4.3 After Westphalia

The Peace of Utrecht (1713) openly named the balance of power as a goal of European order. Emer de Vattel's The Law of Nations (1758) stated the equality of sovereign states. By the 18th century Europe had the core institutions Bull identified: diplomacy, international law, balance of power, war as a regulated activity and the special role of great powers.

5. The Concert of Europe

5.1 The Vienna settlement

After the French Revolutionary and Napoleonic Wars, the Congress of Vienna (1814 to 1815) redrew the map of Europe. Its architects, including Metternich of Austria and Castlereagh of Britain, sought a balance of power and restored monarchies. The Quadruple Alliance of Britain, Austria, Prussia and Russia (1815) agreed to meet regularly; France joined in 1818. Separately, Russia, Austria and Prussia formed the Holy Alliance to defend monarchy and Christian principles.

Concert of Europe: the informal system by which the great powers of Europe, after 1815, consulted at congresses and conferences to manage crises and maintain the balance of power and the territorial settlement, acting as a collective directorate over European affairs.

5.2 How it worked and declined

• Congress phase: Aix-la-Chapelle (1818), Troppau (1820), Laibach (1821) and Verona (1822). Britain broke with the eastern powers over their policy of intervening to crush liberal revolts.
• Conference diplomacy: the powers continued to meet on particular crises, for example the London Conference that recognised Belgian independence (1830 to 1831) and the Congress of Berlin (1878) on the Balkans.
• Decline: the Crimean War (1853 to 1856) set great powers against each other; the unifications of Italy and Germany changed the balance; rigid alliances formed (Triple Alliance, Triple Entente). The system collapsed in 1914.

The Concert matters because it introduced great-power management, an idea that reappeared in the League Council and the UN Security Council.

6. Imperial expansion and decolonisation

6.1 Expansion of European international society

From the 16th to the early 20th century, European states spread their rules across the globe through trade, colonies and conquest. Non-European polities were often not treated as equals. Admission depended on a "standard of civilisation": the ability to protect foreigners' lives and property, keep a European-style legal system, maintain diplomacy and honour international law.

• The Ottoman Empire was formally admitted to the "public law and concert of Europe" by the Treaty of Paris (1856), though capitulations giving foreigners legal privileges continued.
• China was forced into "unequal treaties" after the Opium War (Treaty of Nanking, 1842).
• Japan modernised after 1868, ended its unequal treaties and was recognised as a great power after the Anglo-Japanese Alliance (1902) and its victory over Russia (1905).
• The Berlin Conference (1884 to 1885) set rules for European claims in Africa without African participation.
• The Indian subcontinent passed from the Mughal Empire to East India Company and then British Crown rule (1858).

6.2 Decolonisation

The two world wars weakened the colonial powers. The Atlantic Charter (1941) spoke of the right of peoples to choose their government; the UN Charter (1945) referred to self-determination. Independence came in waves: Asia in the late 1940s (India and Pakistan in 1947, Indonesia in 1949), Africa around 1960, and the Caribbean and Pacific later.

• UN General Assembly Resolution 1514 (1960), the Declaration on the Granting of Independence to Colonial Countries and Peoples, declared colonialism a denial of human rights.
• The Bandung Conference (1955) and the Non-Aligned Movement (1961) gave new states a collective voice; the Group of 77 (1964) and the call for a New International Economic Order (1974) pressed economic demands.
• UN membership grew from 51 founding members in 1945 to 193 today.

Decolonisation made international society global for the first time. New states accepted sovereignty, non-intervention and diplomacy, but challenged racial hierarchy, colonial rule and economic inequality. This is the theme of Bull and Watson's The Expansion of International Society (1984) and its idea of a "revolt against the West".

7. The League and UN era

7.1 The League of Nations

Created by the Covenant, part of the Treaty of Versailles (1919), and inspired by Woodrow Wilson's Fourteen Points. It aimed to replace the balance of power with collective security, settle disputes by arbitration and reduce armaments. Its mandates system placed former German and Ottoman territories under supervised administration. It failed because the United States never joined, decisions needed unanimity, it lacked enforcement, and great powers defied it: Japan in Manchuria (1931) and Italy in Abyssinia (1935 to 1936). It could not prevent the Second World War.

7.2 The United Nations

The UN Charter was signed at San Francisco on 26 June 1945 and came into force on 24 October 1945. It combines the principles of sovereign society with great-power management:

• Article 2(1): sovereign equality of all members.
• Article 2(4): prohibition of the threat or use of force against the territorial integrity or political independence of any state.
• Article 2(7): no intervention in matters essentially within domestic jurisdiction (except enforcement under Chapter VII).
• The Security Council, with five permanent members holding a veto (the United States, the Soviet Union, now Russia, the United Kingdom, France and China), reflects the Concert idea.

The Universal Declaration of Human Rights (1948) placed the individual on the international agenda, adding a "world society" element to a society of states.

8. The Cold War and post-Cold War order

8.1 Cold War (1947 to 1991)

The world divided into two blocs led by the United States and the Soviet Union, formalised in NATO (1949) and the Warsaw Pact (1955). Ideological conflict meant weak solidarity, yet international society survived: the UN continued, diplomacy and treaties worked between rivals (arms control, the Helsinki Final Act of 1975), and nuclear deterrence encouraged rules of restraint. Both superpowers supported sovereignty and decolonisation in principle, while intervening in their spheres (Hungary 1956, Czechoslovakia 1968, Vietnam, Afghanistan 1979). Pakistan joined SEATO (1954) and the Baghdad Pact (1955, renamed CENTO in 1959), while India led non-alignment.

8.2 Post-Cold War (1991 to the present)

• Liberal optimism: the Charter of Paris (1990), the Gulf War (1991) authorised by the Security Council, President Bush's "new world order" and Fukuyama's "end of history".
• Solidarist trends: humanitarian intervention (Somalia, Kosovo 1999), international criminal tribunals and the International Criminal Court (Rome Statute 1998), and the Responsibility to Protect endorsed at the 2005 World Summit.
• Challenges: 9/11 and the war on terror, the 2003 Iraq war without Security Council authorisation, contested intervention in Libya (2011), Russia's actions in Ukraine (2014, 2022).
• Power shift: the rise of China and India, the BRICS grouping, and talk of a multipolar or multi-order world in which Western leadership of international society is questioned.

9. The English School idea of international society

9.1 Origins and key thinkers

The English School grew out of the British Committee on the Theory of International Politics (from 1959). Key figures are Martin Wight, Hedley Bull (The Anarchical Society, 1977), Adam Watson (The Evolution of International Society, 1992) and, more recently, Barry Buzan and Tim Dunne. It takes a middle path between realism and liberalism: the world is anarchic (no world government) but not chaotic, because states share rules and institutions.

9.2 Wight's three traditions

Tradition	Associated thinker	View of international relations
Realism	Hobbes, Machiavelli	International system: a state of war, power dominates
Rationalism	Grotius	International society: states follow shared rules and law
Revolutionism	Kant	World society: humanity as a moral community

9.3 Bull's institutions of international society

1. Balance of power: prevents any one state from dominating.
2. International law: sets out the rules of coexistence.
3. Diplomacy: communication and negotiation.
4. War: as a regulated instrument, controlled by rules on when and how it is fought.
5. Great powers: managing the system through spheres, crisis management and agreements.

Bull identified the basic goals of order as preserving the society of states itself, maintaining the independence of states, keeping peace as the normal condition, limiting violence, keeping promises and stabilising possession.

9.4 Pluralism and solidarism

Pluralism: the view that states have different values and should agree only on minimum rules of coexistence, especially sovereignty and non-intervention.
Solidarism: the view that states can and should agree on wider common values, such as human rights, and act together to enforce them, even by intervention.

The debate between them is central to modern questions such as humanitarian intervention and R2P. Developing states, including Pakistan, have generally defended pluralist principles of sovereignty while supporting solidarist causes like self-determination for Kashmir and Palestine.

9.5 Evaluation

• Strengths: historical depth; explains order without world government; combines power and norms.
• Criticisms: Eurocentric story of "expansion" from Europe; vague methodology; underplays economics and coercion in imperial expansion; constructivists and postcolonial scholars say non-Western societies shaped the system too.

10. Key dates timeline

Date	Event	Significance
14th century BC	Amarna letters	Early diplomacy among great kings
431 to 404 BC	Peloponnesian War	Classic case of power politics among city-states
221 BC	Qin unification of China	End of the Warring States system
1454	Peace of Lodi	Balance of power among Italian states
1555	Peace of Augsburg	Cuius regio, eius religio
1648	Peace of Westphalia	Milestone for sovereignty and the states system
1713	Peace of Utrecht	Balance of power named as a principle
1814 to 1815	Congress of Vienna	Start of the Concert of Europe
1856	Treaty of Paris	Ottoman Empire admitted to the European concert
1884 to 1885	Berlin Conference	Rules for colonial claims in Africa
1919	Treaty of Versailles and League Covenant	First general collective security organisation
1945	UN Charter	Sovereign equality, ban on force, Security Council
1947	Independence of India and Pakistan	Start of large-scale decolonisation
1955	Bandung Conference	Voice of newly independent states
1960	UNGA Resolution 1514	Colonialism declared illegitimate
1991	End of the Soviet Union	End of bipolarity
2005	World Summit endorses R2P	Solidarist limit on sovereignty

11. Two model outlines

Outline 1: "The Peace of Westphalia is the founding moment of modern international society." Discuss.
1. Introduction: define international society (Bull); state thesis that Westphalia was a milestone, not a founding moment.
2. Background: medieval overlapping authority, Reformation, Augsburg 1555, Thirty Years' War.
3. Case for: princes' foreign policy rights, decline of papal authority, religious coexistence, Dutch and Swiss independence, idea of territorial sovereignty.
4. Case against: Empire survived; France and Sweden as guarantors (intervention); sovereignty developed over centuries (Bodin before, Vattel after); Krasner's "organised hypocrisy".
5. Non-European perspective: older systems in Asia, Islamic world; global society only after decolonisation.
6. Conclusion: Westphalia symbolises a long transition; the truly global society dates from 1945 to 1960. Outline 2: How did international society become global, and what were the consequences?
1. Introduction: from a European to a global society of states.
2. Expansion: trade, empire, the standard of civilisation, unequal treaties; Ottoman, Japanese and Chinese entry.
3. Decolonisation: world wars, Atlantic Charter, UN Charter, Resolution 1514, India and Pakistan 1947, Bandung and NAM.
4. Consequences: universal sovereignty and non-intervention; UN membership from 51 to 193; new agendas (development, racial equality, self-determination); weaker cultural unity (Bull's concern); North-South divisions.
5. Current debates: rise of non-Western powers, pluralism versus solidarism, R2P.
6. Conclusion: a global but more diverse and contested international society.

Quick check

1. Define international system and international society, and explain the difference between them.
2. Describe two features of the Amarna system that show an early form of international society.
3. Explain why medieval Europe was not a system of sovereign states.
4. State three outcomes of the Peace of Westphalia.
5. Explain why some scholars call the importance of 1648 a "myth".
6. Describe how the Concert of Europe worked and give two reasons for its decline.
7. Explain the "standard of civilisation" and give one example of how it affected a non-European state.
8. Explain two reasons why the League of Nations failed.
9. Describe how the UN Charter combines sovereign equality with great-power management.
10. Distinguish between pluralism and solidarism, using the Responsibility to Protect as an example.
11. Evaluate the claim that the English School gives a Eurocentric account of international society.

1. An international system exists when states have enough contact and impact on one another's decisions to behave as parts of a whole. An international society exists when states, conscious of common interests and values, consider themselves bound by common rules and share in common institutions. The difference: a system involves interaction only; a society involves shared rules and institutions accepted as binding, such as diplomacy and international law.

2. Any two of: the great kings addressed one another as "brother", recognising each other as equals; they exchanged envoys and messengers, who were generally protected; they exchanged gifts and arranged marriages according to accepted conventions; they distinguished great kings from vassal rulers, an early idea of great-power status.

3. Authority was overlapping, not exclusive. The Pope claimed spiritual supremacy and the Emperor a universal secular role, while kings, lords, bishops and cities held layered rights. People could owe loyalty to several superiors, and territory was not under one exclusive authority. Sovereignty, meaning supreme authority within a territory and independence from outside, did not yet exist.

4. Any three of: end of the Thirty Years' War; German princes gained the right to make alliances and conduct foreign policy; the Augsburg religious settlement was confirmed and extended to Calvinists; Dutch independence from Spain was recognised; Swiss independence confirmed; papal objections were ignored, showing the decline of religious authority over rulers.

5. Critics such as Osiander and Krasner point out that the treaties did not create sovereign equality: they preserved the Holy Roman Empire and gave France and Sweden the right to guarantee its constitution, which allowed outside interference. Ideas of sovereignty came before (Bodin, 1576) and developed long after (Vattel, 1758), and powerful states continued to intervene. So 1648 is better seen as one stage in a long process.

6. After 1815 the great powers (Britain, Austria, Prussia, Russia, and France from 1818) met at congresses and conferences to manage crises and preserve the Vienna settlement and the balance of power, for example at Aix-la-Chapelle (1818) and the Congress of Berlin (1878). Reasons for decline, any two: Britain opposed the eastern powers' interventions against liberal revolts in the 1820s; the Crimean War (1853 to 1856) pitted great powers against each other; Italian and German unification upset the balance; rigid alliance blocs replaced consultation, ending in 1914.

7. The standard of civilisation was the test Europeans used to decide whether a non-European state could join international society as an equal: protecting foreigners' life and property, a European-style legal system, regular diplomacy and observance of international law. Example: China was forced into unequal treaties such as Nanking (1842) and foreigners enjoyed extraterritorial rights; alternatively, Japan reformed its law and institutions after 1868, ended its unequal treaties and was accepted as a great power by 1905.

8. Any two: the United States never joined, so it lacked a leading power; decisions needed unanimity, causing paralysis; it had no armed force of its own and relied on members' willingness to impose sanctions; great powers defied it without consequence, as Japan did in Manchuria (1931) and Italy in Abyssinia (1935 to 1936).

9. Article 2(1) affirms sovereign equality, Article 2(4) bans the use of force against other states and Article 2(7) protects domestic jurisdiction: these reflect a society of equal sovereigns. At the same time, the Security Council gives five permanent members a veto and primary responsibility for peace and security, with power to authorise enforcement under Chapter VII. This continues the Concert idea that great powers have special rights and duties in managing order.

10. Pluralism holds that states differ in values and should agree only on minimum rules of coexistence, above all sovereignty and non-intervention. Solidarism holds that states share wider values such as human rights and may act together to enforce them. R2P (2005) is a solidarist step: it says sovereignty includes a responsibility to protect populations from genocide, war crimes, ethnic cleansing and crimes against humanity, and that the international community may act through the Security Council if a state fails. Pluralists fear such ideas can be abused for intervention, as many states argued after Libya (2011).

11. For: the classic English School story describes international society expanding outward from Europe, treating Europe as the model and other peoples as entrants; the standard of civilisation is discussed with little attention to the violence of empire; non-European systems such as the Islamic siyar or the Chinese tributary order receive less attention. Against: Bull and Watson studied the "revolt against the West" and decolonisation seriously; Watson's work compares many ancient systems; later writers such as Buzan and Dunne have broadened the approach to global and regional international societies. Judgement: the early English School was Eurocentric in focus, but its concepts (rules, institutions, pluralism and solidarism) can be applied to non-Western history, and recent work has partly corrected the bias.