3.1 The First World War, 1914–18

3 – Depth Study A: The First World War, 1914‑18 (Cambridge IGCSE History 0470)

1. Introduction

The First World War (1914‑1918) was a global conflict that involved the great powers of Europe, their overseas empires and several non‑European states. It reshaped borders, societies and the nature of warfare. Mastery of its causes, main events, technology, home‑front experience and consequences is essential for the IGCSE syllabus.

2. Causes of the War

• Long‑term (structural) causes
  • Nationalism – intense pride and rivalry, especially in the Balkans.
  • Imperialism – competition for colonies in Africa and Asia.
  • Militarism – naval and arms race, notably between Britain and Germany.
  • Alliance systems – Triple Entente (France, Russia, Britain) vs. Triple Alliance (Germany, Austria‑Hungary, Italy).
• Immediate (trigger) causes
  • Assassination of Archduke Franz Ferdinand (28 June 1914) in Sarajevo.
  • Austro‑Hungarian ultimatum to Serbia and declaration of war.
  • Chain reaction of mobilisations caused by alliance commitments.

3. Early Western Front (1914)

3.1 The Schlieffen Plan and its failure

• German strategy to avoid a two‑front war: a rapid sweep through Belgium, then south‑west to encircle Paris and force France to surrender before Russia could fully mobilise.
• Execution in August 1914 was slowed by Belgian resistance, the unexpected speed of the British Expeditionary Force (BEF) deployment and logistical problems.
• Result: the German advance stalled at the Battle of Mons (23‑24 August) and was halted at the First Battle of the Marne (5‑12 September), forcing a retreat and the start of trench warfare.

3.2 Race to the Sea and the First Battle of Ypres

• After the Marne both sides tried to outflank each other northwards, digging successive trench lines – the “Race to the Sea”.
• By October 1914 the front had stabilised from the North Sea to Switzerland.
• First Battle of Ypres (19 October – 22 November 1914) – the BEF, French and Belgian troops stopped the German advance to the Channel ports, cementing the stalemate on the Western Front.

3.3 Why the Western Front became a defensive war

• Trench technology – deep, zig‑zagging networks protected infantry from machine‑gun fire.
• Artillery dominance – long‑range guns could devastate attacking troops before they reached the enemy line; the development of the creeping barrage required careful coordination and favoured the defender.
• Machine‑gun firepower – a single gun could halt an entire infantry wave, making rapid manoeuvre impossible.
• Logistical constraints – railways and supply lines could not keep pace with the speed required for a decisive breakthrough after the Race to the Sea.
• Combined, these factors turned the Western Front into a static, attritional war that lasted until 1918.

4. Major Fronts and Key Battles (1914‑1918)

4.1 Western Front (France & Belgium)

• Static trench system from 1914 to 1918; “war of attrition”.
• Key battles
  • Battle of Mons (1914) – first British engagement.
  • First Battle of the Marne (1914) – halted the Schlieffen Plan.
  • First Battle of Ypres (1914) – established the trench line.
  • Verdun (Feb – Dec 1916) – longest battle, symbol of French determination.
  • Somme (1 July – 18 Nov 1916) – massive casualties, first use of tanks.
  • Passchendaele (31 July – 10 Nov 1917) – mud, attrition, Allied breakthrough.
  • German Spring Offensive (Mar – July 1918) – three phases (Operation Michael, Georgette, Blücher‑Yorck) aimed at splitting the British and French armies before the full arrival of US forces.
  • Hundred Days Offensive (Aug – Nov 1918) – Allied series of attacks leading to the armistice.

4.2 Eastern Front (Russia vs. Germany & Austria‑Hungary)

• More fluid movement across a vast territory.
• Key battles
  • Tannenberg (26 – 30 August 1914) – decisive German victory.
  • Masurian Lakes (2 – 16 September 1914) – reinforced German success.
  • Brusilov Offensive (June – Sept 1916) – huge Russian gains, huge Austro‑Hungarian losses.

4.3 Other Theatres

• Italian Front – battles along the Isonzo River (1915‑1917).
• Middle East – Gallipoli (1915), Mesopotamian campaign, Arab Revolt (1916‑1918).
• Naval warfare – blockades, unrestricted U‑boat submarine warfare, Battle of Jutland (31 May – 1 June 1916).
• British‑Empire troops – Indian, Canadian, Australian, New Zealand and South‑African forces; South‑African units fought on the Western Front (e.g., 1st South African Infantry Brigade) and in East Africa.
• Japanese contribution – seized German possessions in the Pacific and escorted Allied shipping in the Indian Ocean.
• Air operations over the Western Front – reconnaissance, tactical bombing and fighter combat (e.g., the “air war” of 1917‑1918).

5. Technology and the Conduct of War

• Machine guns – gave defenders overwhelming firepower.
• Artillery – long‑range bombardments; creeping‑barrage tactics.
• Poison gas – chlorine, phosgene, mustard; caused severe injuries and terror.
• Tanks – first used by Britain at the Somme (1916) to cross trenches.
• Aircraft – reconnaissance, tactical bombing, dogfights over the Western Front.
• Submarines (U‑boats) – unrestricted warfare aimed at cutting Allied supply lines, leading to the US entry.

6. The Home Front

Both the Allied and Central Powers mobilised entire societies for total war.

• Conscription – Britain (1916), France (1913), Germany (1915), Russia (1915), Italy (1915), United States (1917).
• Rationing – food, fuel, clothing controlled by the state.
• War propaganda – posters, newspapers, speeches to sustain morale and recruit.
• Women’s roles – factory work, nursing, auxiliary services (e.g., Women’s Army Auxiliary Corps); laid foundations for post‑war suffrage.
• Economic strain – inflation, public debt, post‑war recession.

6.1 Civilian impact by theatre

7. Why Germany Asked for an Armistice in 1918

• US entry (April 1917) – fresh manpower and material tipped the balance in favour of the Allies.
• German Spring Offensive (March – July 1918)
  • Three phases: Operation Michael (the main thrust in the Somme sector), Operation Georgette (the “Lys Offensive” in Flanders), and Operation Blücher‑Yorck (the push towards the Marne).
  • Strategic aim: deliver a decisive blow that would split the British and French armies before the United States could be fully deployed.
  • Initial territorial gains exhausted German troops, over‑stretched supply lines and caused very high casualties.
  • Allied counter‑offensive (the Hundred Days Offensive) from August 1918 reversed the advances and pushed the Germans back.
• German Revolution (Nov 1918) – mutinies in the navy (the Kiel mutiny), workers’ councils and widespread political unrest made continued fighting impossible.
• Armistice (11 Nov 1918) – Germany accepted the cease‑fire to avoid total military and civil collapse.

8. End of the War and the Treaty of Versailles

The armistice on 11 November 1918 ended hostilities. The peace settlement was formalised in the Treaty of Versailles (28 June 1919).

• Territorial changes – Alsace‑Lorraine returned to France; new states created (Poland, Czechoslovakia, Yugoslavia); German colonies transferred to League of Nations mandates.
• Military restrictions – German army limited to 100 000 men; no air force, tanks or submarines; Rhineland demilitarised.
• Reparations – Germany required to pay large sums (later set at 132 billion gold marks), causing severe economic hardship.
• League of Nations – established to prevent future wars (the United States did not join).

9. Consequences and Legacy

1. Political – collapse of the Russian, Ottoman, Austro‑Hungarian and German empires; rise of new nation‑states and the principle of self‑determination.
2. Social – loss of a generation; changed gender roles; widespread trauma (shell‑shock); growth of pacifist movements.
3. Economic – massive debts, hyperinflation in Germany, global recession in the early 1920s.
4. International – harsh terms of Versailles sowed resentment, contributing to the outbreak of the Second World War.

10. To What Extent Was It a World War? (Assessment)

While the decisive battles were fought in Europe, the war truly became “world‑wide” because:

• European powers – Britain, France, Germany, Russia and Italy mobilised resources from their global empires.
• British‑Empire troops – soldiers from India, South Africa, Canada, Australia, New Zealand and other colonies fought on the Western Front, in the Middle East and in Africa.
• United States – entered in 1917, providing fresh troops and material that altered the strategic balance.
• Japan – seized German possessions in the Pacific and protected Allied shipping in the Indian Ocean.
• Arab Revolt – coordinated with the British to undermine Ottoman control in the Middle East.
• Naval and air warfare – blockades and U‑boat campaigns affected global trade; air operations extended the reach of combat.

Overall, the war was European in its origins and main battlefields, but the mobilisation of colonies, the involvement of non‑European powers and the global economic impact mean it can be assessed as a truly world war, albeit with a European centre.

11. Revision Checklist

• Explain both long‑term and immediate causes of the war.
• Describe the Schlieffen Plan, why it failed and how it led to trench stalemate.
• Explain why the Western Front became a defensive war after the “Race to the Sea”.
• Recall at least three major battles (e.g., Mons, Marne, Verdun, Somme, Passchendaele) and their outcomes.
• Analyse how new technology (machine guns, artillery, gas, tanks, aircraft, U‑boats) changed combat.
• Discuss the contribution of British‑Empire troops, including South‑African forces, and the role of Japan and the Arab Revolt – answering “To what extent was it a world war?”.
• Explain the importance of other fronts (Eastern, naval, Gallipoli, Middle East) and their civilian impact.
• Detail the 1918 German Spring Offensive, why it failed and why Germany sought an armistice, linking the German Revolution to the decision.
• Summarise the main terms of the Treaty of Versailles and evaluate its long‑term effects.
• Assess the political, social, economic and international legacy of the First World War.