World Wars, Colonisation and Decolonisation

Prerequisites: Age of Revolutions and Political Ideologies · World History — overview

The Hook: Eighty Years of the United Nations

The Core Concept

1. Imperialism and colonisation (19th century to 1914)

• Drivers: industrial demand for raw materials and markets; surplus capital; strategic rivalry; nationalism and racial ideologies (“civilising mission”); technology (steamships, quinine, machine guns, telegraph).
• Africa — the “Scramble”: the Berlin Conference (1884–85) laid down rules for European claims. By 1914, only Ethiopia (which defeated Italy at Adwa, 1896) and Liberia remained independent.
• Asia: British India; French Indochina; Dutch East Indies. China was forced open by the Opium Wars (1839–42; 1856–60) — the Treaty of Nanking (1842) ceded Hong Kong to Britain — and carved into spheres of influence. Japan, after the Meiji Restoration (1868), industrialised and became an imperial power; its victory in the Russo-Japanese War (1904–05) inspired Asian nationalists, including in India.
• Forms: settler colonies, colonies of exploitation, protectorates, spheres of influence.

2. The First World War (1914–1918)

Causes — “MAIN”: Militarism (arms race, Anglo-German naval rivalry), Alliances (Triple Alliance, 1882: Germany, Austria-Hungary, Italy; Triple Entente, 1907: Britain, France, Russia), Imperialism (colonial rivalries, Moroccan crises), Nationalism (Balkan nationalism, French revanchism over Alsace-Lorraine).

Spark: assassination of Archduke Franz Ferdinand of Austria-Hungary at Sarajevo, 28 June 1914; Austria-Hungary declared war on Serbia on 28 July 1914.

Course: trench warfare on the Western Front; the USA entered in April 1917; Russia left after the Bolshevik revolution (Brest-Litovsk, 1918); armistice on 11 November 1918.

Peace settlement (Paris Peace Conference, 1919–20):

Outcomes: four empires collapsed (German, Austro-Hungarian, Ottoman, Russian); new states — Poland, Czechoslovakia, the Kingdom of Serbs, Croats and Slovenes (later Yugoslavia), Finland and the Baltic states; President Wilson’s Fourteen Points (January 1918) and the League of Nations (1920), which the USA never joined; the ILO (1919). The Sykes–Picot Agreement (1916) and the Balfour Declaration (1917) shaped the modern Middle East.

India and the war: more than a million Indians served overseas; the war brought price rise and recruitment pressure; the Montagu Declaration (August 1917) promised “responsible government”; Turkey’s treatment fed the Khilafat movement. India signed the Treaty of Versailles and was a founding member of the League of Nations.

3. The inter-war crisis (1919–1939)

• Great Depression: the Wall Street Crash (October 1929) led to mass unemployment worldwide; the US response was Roosevelt’s New Deal (from 1933).
• Rise of dictatorships: Mussolini’s March on Rome (1922); Hitler became Chancellor (January 1933); militarism in Japan.
• Aggression and appeasement: Japan invaded Manchuria (1931); Italy invaded Ethiopia (1935); Germany remilitarised the Rhineland (1936); Spanish Civil War (1936–39); Anschluss with Austria (March 1938); Munich Agreement (September 1938) conceded the Sudetenland; Nazi–Soviet Non-Aggression Pact (August 1939).
• Why the League failed: no US membership; decisions required unanimity; no armed force; great powers left or ignored it (Japan, Germany, Italy).

4. The Second World War (1939–1945)

The Holocaust — the Nazi genocide of about six million Jews, along with Roma, disabled people and others — led directly to the Genocide Convention (1948) and the Universal Declaration of Human Rights (1948).

Post-war order: the UN Charter signed at San Francisco (26 June 1945), in force 24 October 1945; Bretton Woods (July 1944) created the IMF and the World Bank; GATT (1947); the Nuremberg trials (1945–46).

5. Redrawal of boundaries

6. The Cold War (1947–1991)

• Blocs and doctrines: Truman Doctrine (1947) and containment; Marshall Plan (1948); Berlin Blockade (1948–49); NATO (April 1949) versus the Warsaw Pact (1955).
• Flashpoints: Korean War (1950–53); Cuban Missile Crisis (October 1962); Vietnam War (to the fall of Saigon, 1975); Soviet intervention in Afghanistan (1979).
• Arms race and détente: nuclear and space competition; SALT I (1972).
• End: Gorbachev’s glasnost (openness) and perestroika (restructuring) from 1985; fall of the Berlin Wall (9 November 1989); dissolution of the USSR (December 1991).

7. Decolonisation (1945–1990s)

Why empires ended: European powers were economically exhausted by the war; nationalist movements had matured; the USA and USSR both opposed old-style colonialism; the UN gave colonies a platform (UNGA Resolution 1514, December 1960 — Declaration on the Granting of Independence to Colonial Countries and Peoples); India’s independence (1947) set a powerful precedent.

Solidarity of the newly independent: the Bandung Conference (April 1955) of 29 Asian and African countries; the Non-Aligned Movement, founded at Belgrade (1961) under Nehru, Tito (Yugoslavia), Nasser (Egypt), Sukarno (Indonesia) and Nkrumah (Ghana).

Neo-colonialism: Nkrumah and others argued that formal independence often left economic dependence intact — through commodity exports, debt and foreign control of resources.

graph TD
    A["Imperial rivalry, alliances"] --> B["First World War 1914-18"]
    B --> C["Versailles, League, mandates"]
    C --> D["Depression and fascism"]
    D --> E["Second World War 1939-45"]
    E --> F["UN, Bretton Woods"]
    E --> G["Cold War blocs"]
    E --> H["Decolonisation: Asia 1940s, Africa 1950s-60s"]
    H --> I["Bandung 1955, NAM 1961"]
    G --> J["End of Cold War 1989-91"]

Memory Anchors

Causes of the First World War — “MAIN”: Militarism, Alliances, Imperialism, Nationalism.

Versailles on Germany — “BRAG”: Blame (war guilt), Reparations, Army cut to 100,000, Ground lost (Alsace-Lorraine, colonies, Rhineland demilitarised).

NAM founders — “NTNSN”: Nehru, Tito, Nasser, Sukarno, Nkrumah.

Decolonisation waves — “Asia in the forties, Africa in the sixties, Portugal last of the old empires in the seventies.”

One-line Mains hook: The world wars were fought to preserve the balance of power in Europe; their most lasting result was the end of Europe’s power over the world.

For Prelims

Prelims occasionally tests these facts:

For Mains

• Dimensions: causes (structural vs immediate); consequences (political, economic, territorial, humanitarian); international institutions (League vs UN); ideology (fascism, communism, liberal democracy); the colonial world (contribution of colonial soldiers, nationalism, decolonisation); India’s role (war contribution, NAM, Panchsheel).
• Keywords: balance of power, appeasement, collective security, self-determination, mandate system, containment, bipolarity, détente, non-alignment, neo-colonialism.
• Value-addition: the punitive Versailles settlement as a cause of the Second World War (Keynes’s critique of reparations in The Economic Consequences of the Peace, 1919); the Atlantic Charter’s self-determination clause and Churchill’s reluctance to apply it to India; India’s leadership at Bandung and in NAM.

Common Traps

In the News

• October 2025 — the United Nations marked the 80th anniversary of the coming into force of its Charter (24 October 1945).

Practice

Prelims

Mains

Quick Revision

Key Takeaways

Related Topics

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