Edexcel IGCSE History: The Origins and Course of the First World War, 1905–18 — Revision Notes

Quick-recall notes for Historical Investigation A1 of Pearson Edexcel International GCSE History 4HI1 Paper 2, “The origins and course of the First World War, 1905–18”. The full explanation is in the A1 study guide; practise the source questions with the A1 practice questions.

Syllabus coverage (4HI1, Investigation A1)

Key topic	Core content
1. Alliances and rivalry, 1905–14	Triple Alliance, Triple Entente; economic, imperial, military rivalry
2. Growth of tension, 1905–14	Bosnian Crisis, Balkan Wars, naval race, Moroccan Crises, Sarajevo, July Crisis
3. Schlieffen Plan and deadlock	Plan and failure, trenches, weapons, Somme, Passchendaele, Haig
4. War at sea and Gallipoli	Raids, Heligoland Bight, Dogger Bank, Jutland, U-boats, Lusitania, Gallipoli
5. Defeat of Germany	US entry, Ludendorff offensive, Allied advance, reasons for defeat

Timeline

Date	Event
1882	Triple Alliance
1894	Franco-Russian Alliance
1904	Entente Cordiale
1905–06	First Moroccan Crisis; Algeciras Conference
1906	HMS Dreadnought launched
1907	Anglo-Russian Entente completes the Triple Entente
1908–09	Bosnian Crisis
1911	Agadir (Second Moroccan) Crisis
1912–13	Balkan Wars
28 June 1914	Assassination at Sarajevo
28 July 1914	Austria-Hungary declares war on Serbia
4 Aug 1914	Britain declares war on Germany
Sept 1914	Battle of the Marne; Schlieffen Plan fails
Dec 1914	Raids on Scarborough, Hartlepool and Whitby
Jan 1915	Battle of Dogger Bank
Apr 1915	Gas at Ypres; Gallipoli landings
May 1915	Lusitania sunk
Dec 1915–Jan 1916	Gallipoli evacuation
May–June 1916	Battle of Jutland
July–Nov 1916	Battle of the Somme
Feb 1917	Unrestricted submarine warfare
Apr 1917	USA enters the war
July–Nov 1917	Passchendaele
Mar 1918	Ludendorff spring offensive
Aug 1918	Battle of Amiens
11 Nov 1918	Armistice

Key terms

Term	Meaning
Entente	Friendly understanding, not a binding alliance
Dreadnought	All-big-gun battleship that made older ships obsolete
Weltpolitik	German “world policy” of colonial and naval expansion
Blank cheque	Germany’s promise of unconditional support to Austria, July 1914
Schlieffen Plan	German plan to defeat France quickly through Belgium
Stalemate / deadlock	Neither side able to break through
Attrition	Wearing the enemy down by casualties
Convoy	Merchant ships sailing together under naval escort
ANZAC	Australian and New Zealand Army Corps
Stormtroopers	German assault troops used in 1918

Why deadlock? A five-point answer

1. Defensive firepower — machine guns, artillery, barbed wire.
2. Railways moved defending reserves faster than attackers could advance on foot.
3. Communication broke down once troops left their trenches.
4. New weapons (gas, early tanks) were unreliable and both sides adapted.
5. Generals’ tactics — long bombardments warned the enemy and churned up ground.

Source skills for this option

• Features question (6): two features, each with supporting detail — e.g. two features of the Moroccan Crises or of life in the trenches.
• Cross-reference (8): find specific agreement and disagreement between two sources, then judge “how far”. Use context: a 1916 newspaper under censorship will play down losses.
• Interpretation (16): test the historian’s view against the sources and your own knowledge, e.g. whether Haig was responsible for the losses on the Somme.

Worked example: cross-referencing

Two invented sources: Source A, a British general’s diary, says the first day of the Somme “went well in places, though losses were heavy”. Source B, a soldier’s later memoir, says “whole battalions were cut down before they reached the wire”.

Agreement: both accept heavy losses. Disagreement: A suggests partial success; B suggests total failure. Context: the general’s position and the date of writing explain the guarded tone, while own knowledge (about 57,000 British casualties on 1 July 1916) supports B on scale but not on the whole front — some southern sectors did advance. Judgement: partly supports.

Common mistakes and exam traps

• Writing about usefulness or reliability on its own. The 8-mark question is about how far one source supports another.
• Treating the alliances as automatic. Britain was not bound to fight in 1914; Belgium was the trigger for its entry.
• Ignoring the Balkans. The war began in the Balkans; know 1908–09 and 1912–13.
• Seeing Jutland as a German victory. Tactically perhaps, but strategically Britain kept control of the North Sea.
• Forgetting the home front’s role in 1918. The blockade and unrest in Germany help explain defeat.

Frequently asked questions

What was the main cause of the war? There is no single answer; build an argument linking long-term rivalry to the July Crisis decisions.

Why did Gallipoli fail? Poor planning, delays that let the Ottomans prepare, difficult terrain and strong Turkish defence.

Why did the USA join in 1917? Unrestricted submarine warfare and the Zimmermann Telegram.

Source

Pearson Edexcel International GCSE History (4HI1) specification, Issue 5, February 2026, Paper 2, Historical Investigation A1.