World Wars, Decolonisation and the Cold War

Big picture

The 20th century saw two world wars, the collapse of empires, the redrawing of national boundaries, the rise of the USA and USSR, decolonisation in Asia and Africa, and the Cold War. Knowing causes → events → effects gives you material for essays and GS1/GS2 answers.

1. The First World War (1914–1918)

Causes – remember "MAIN":

• Militarism – an arms race, especially the naval race between Britain and Germany;
• Alliances – the Triple Alliance (Germany, Austria-Hungary, Italy) and the Triple Entente (Britain, France, Russia);
• Imperialism – rivalry for colonies (the Moroccan crises);
• Nationalism – pan-Slavism, the Balkan conflicts.

Immediate cause: the assassination of Archduke Franz Ferdinand at Sarajevo (28 June 1914).

Course: trench warfare on the Western Front; new weapons (machine guns, poison gas, tanks, submarines); the USA joined in 1917; Russia exited after the Revolution (Treaty of Brest-Litovsk, 1918).

Effects:

• about 15–20 million deaths;
• the fall of four empires (German, Austro-Hungarian, Ottoman, Russian);
• the Treaty of Versailles (1919) – harsh on Germany (war guilt clause, reparations, loss of territory);
• the League of Nations;
• new states (Poland, Czechoslovakia, Yugoslavia);
• Arab lands placed under mandates (Britain and France);
• India's role: about 1.3 million Indian soldiers served; the war fuelled nationalism (the Home Rule movement, Khilafat).

2. The Russian Revolution (1917)

Causes: autocracy of the Tsar, poverty of peasants and workers, defeat in war, food shortages. The February Revolution removed the Tsar; the October Revolution brought the Bolsheviks (Lenin) to power – "peace, land and bread".

Effects: the first communist state (the USSR, 1922); planned economy (Five-Year Plans under Stalin); collectivisation and repression; inspiration to anti-colonial movements and to India's planning.

3. Between the wars

• The Great Depression (1929) – the Wall Street crash → mass unemployment worldwide; the New Deal in the USA (Roosevelt) and Keynesian economics (government spending to create demand).
• The rise of fascism (Mussolini, Italy 1922) and Nazism (Hitler, 1933): extreme nationalism, racism, dictatorship, expansion.
• The failure of the League of Nations (Manchuria 1931, Abyssinia 1935); appeasement (the Munich Agreement 1938).

4. The Second World War (1939–1945)

Causes: the harsh Versailles treaty; the Depression; fascist expansionism; the failure of the League; appeasement; the Nazi–Soviet Pact (1939).

Trigger: Germany invaded Poland (1 September 1939).

Key events: the fall of France (1940); the Battle of Britain; Germany's invasion of the USSR (1941); Pearl Harbor (December 1941) brought the US in; Stalingrad (1942–43, the turning point); D-Day (June 1944); the Holocaust; the atomic bombings of Hiroshima and Nagasaki (August 1945).

Effects:

• 60–70 million deaths;
• the United Nations (1945);
• two superpowers;
• a weakened Britain, which speeded India's independence;
• Bretton Woods institutions (the IMF and World Bank, 1944);
• the Universal Declaration of Human Rights (1948);
• the division of Germany and Korea.

5. Decolonisation

Why it happened: nationalist movements; the post-war weakness of colonial powers; US and Soviet anti-colonial positions; the UN (Declaration on Granting Independence, 1960); India's example. Afro-Asian solidarity: the Bandung Conference (1955), NAM (1961).

6. The Cold War (1947–1991)

A conflict between the US-led capitalist bloc and the Soviet-led communist bloc – fought through ideology, arms races, proxy wars and space rather than direct war.

India's position: non-alignment – independence in foreign policy, not neutrality; the Indo-Soviet Treaty (1971) during the Bangladesh crisis.

Case study: the redrawn map of West Asia

The secret Sykes–Picot Agreement (1916) divided Ottoman Arab lands between Britain and France. The Balfour Declaration (1917) supported a "national home for the Jewish people" in Palestine. These commitments created mandates with artificial borders and conflicting promises, which shaped the Arab–Israeli conflict (1948 onwards) and instability in Iraq and Syria. This is a classic example of the "redrawal of national boundaries" mentioned in the syllabus.

Common misconceptions

• "The League of Nations failed because the US led it badly." – The US never joined. Its lack of an army and unanimity rules were the main weaknesses.
• "Non-alignment meant India avoided all international issues." – India was active – the Korean armistice, UN peacekeeping, decolonisation.
• "The Cold War was only between the US and USSR." – Most fighting happened in proxy wars in Asia, Africa and Latin America.

How UPSC asks it

Mains GS1 asks about the causes and consequences of the world wars, the role of decolonisation, the impact of the Cold War on newly independent countries, and why the Soviet Union collapsed.

Mains answer framework

Q-type: "To what extent was the Treaty of Versailles responsible for the Second World War?"

• Intro: the 1919 terms in brief.
• Responsible: humiliation, reparations, territorial losses → resentment exploited by Hitler.
• Other causes: the Depression, fascism, the League's weakness, appeasement, the Nazi–Soviet pact.
• Conclusion: a necessary but not sufficient cause; lesson – a just peace prevents future war (contrast with the post-1945 Marshall Plan).

Causes of the two World Wars compared

Decolonisation in Asia and Africa

India's independence in 1947 inspired others. Indonesia (1949), Ghana (1957, one of the first colonies in sub-Saharan Africa to win independence) and many African nations in the 1960s followed. The Bandung Conference (1955) and the Non-Aligned Movement (Belgrade, 1961) gave new nations a collective voice.

Cold War milestones

Mains practice question

Q. How did India's policy of non-alignment serve its interests during the Cold War? Outline: freedom of decision; aid and technology from both blocs; leadership of newly independent countries; limits exposed in 1962; the 1971 Indo-Soviet Treaty as a pragmatic adjustment.

Check your understanding

1. Why did the League of Nations fail? The absence of the United States, lack of an armed force, the need for unanimity and the aggression of Japan, Italy and Germany in the 1930s.
2. What was the Marshall Plan? US economic aid to rebuild Western Europe after 1947, which also aimed to contain communism.