Conflict and Tension: The First World War, 1894–1918

How this unit works

This is your Paper 1 Section B wider world depth study (option 1B/A): 40 marks, about 60 minutes, four questions. Q1 — how useful is Source A (4 marks); Q2 — how useful are Sources B and C (8); Q3 — write an account (8); Q4 — the “main reason” essay (16). The question methods live in the Exam Skills section; this unit supplies the knowledge. Four features of this exam shape how you revise:

1. Twelve of the forty marks are pure source work (Q1–Q2). This option has a distinctive source problem: almost everything published during the war passed through censorship, and almost everything published afterwards was written knowing how it ended. The Source Workbench at the end sets out what each type of source can and cannot show.
2. Q4 names a “main reason” and asks how far you agree. The three great questions — why the war broke out, why the stalemate lasted, why Germany was defeated — are all genuinely argued over. The factor hierarchies at the end give you ranked sets for each.
3. This is a depth study, so precision is marked. You are expected to know dates, places, figures and named individuals — the Entente Cordiale, Agadir, the blank cheque, the Marne, Verdun, Jutland, Amiens. Q3 asks for a connected causal narrative, not a list.
4. Casualty figures for this war are estimates, and often contested ones. Records were destroyed, armies defined “casualty” differently, and totals were politically sensitive. Every disputed figure in this unit is given as a range with the reason stated — do the same in your answers.

The questions historians genuinely argue over

Timeline: the dates you must place

Learn the order before the detail — the sections explain each event. In a depth study, dates are marked.

Part one — the causes, 1879–1914

Part two — stalemate, 1914–1917

Part three — ending the war, 1917–1918

Key people

Before the war

During the war

Key vocabulary

Defined here once and used throughout. The first row is the single most important definition in the unit.

Chapter 1 — The causes of the First World War

This chapter does two things at once. It explains the long-term conditions — alliances, rivalries, armaments, nationalism — that made a general war possible, and the specific sequence of decisions in the summer of 1914 that turned possibility into fact. Neither half works alone: the conditions had existed for years without producing war, and the July Crisis makes no sense without them.

1.1 The alliance web

Bismarck's system. After Germany defeated France in 1871 and annexed Alsace-Lorraine, Bismarck assumed France would seek revenge. His entire foreign policy was designed to keep France isolated — without allies, and therefore unable to fight. The Dual Alliance (1879) bound Germany and Austria-Hungary against Russian attack; the Triple Alliance (1882) added Italy — always the weakest link (it had claims against Austria-Hungary, made a secret understanding with France in 1902, stayed out in 1914 and joined the other side in 1915); and the Reinsurance Treaty (1887) kept Russia friendly despite its Balkan rivalry with Austria-Hungary. Wilhelm II dismantled it: he dismissed Bismarck in 1890 and let the Reinsurance Treaty lapse — leaving Russia without a German connection, needing loans and needing a partner. The Franco-Russian Alliance (1894) followed: French capital financed Russian railways and industry, and each committed to mobilise if the other was attacked by Germany. Bismarck's nightmare had arrived — Germany now faced a possible war on two fronts, and every later German military plan, above all the Schlieffen Plan (see 1.8), exists to solve that problem.

Britain's ententes were different in kind. The Entente Cordiale (1904) settled colonial disputes with France — Britain recognised French primacy in Morocco, France recognised British control in Egypt. The Anglo-Russian Entente (1907) settled Persia, Afghanistan and Tibet. Together with the Franco-Russian Alliance these formed the Triple Entente — but the ententes were understandings, not binding military treaties. That is why Britain's position in July 1914 was genuinely uncertain, why Germany hoped Britain might stay out, and why Britain's entry eventually rested on Belgium (see 1.8). But do not understate them either: from 1906 Britain and France held secret military and naval conversations, and the French fleet concentrated in the Mediterranean while the Royal Navy covered the Channel — so by 1914 France's northern coast was undefended because of an arrangement made with Britain, a moral obligation ministers felt keenly.

1.2 Crises as rehearsals: Morocco and the Balkans

• First Moroccan Crisis, 1905–06. Wilhelm II landed at Tangier (March 1905) and made a speech supporting Moroccan independence — a deliberate challenge, calculated to show France that Britain would not back it over a colonial matter and so break the Entente. Germany demanded a conference, got one at Algeciras (1906) — and lost: only Austria-Hungary supported it; Britain, Russia, Italy and Spain backed France. Germany had tried to break the Entente and instead strengthened it — and frightened Britain into starting the military conversations that year.
• Bosnian Crisis, 1908–09. Austria-Hungary formally annexed Bosnia-Herzegovina (occupied since 1878, still legally Ottoman). Serbia was outraged — Bosnia had a large Serb population. Russia was humiliated — its foreign minister believed he had been promised compensation and got nothing; when Russia prepared to support Serbia, Germany intervened on Austria's side in terms Russia read as an ultimatum, and Russia — still weak after defeat by Japan and the 1905 revolution — backed down. The effects: Russia resolved never to be humiliated again (directly visible in July 1914) and began major military expansion; Serbia's hostility hardened; Germany learned that unconditional backing of Austria worked; and Austria-Hungary learned that firmness paid.
• Agadir Crisis, 1911. French troops entered the Moroccan interior; Germany sent the gunboat Panther to Agadir. Germany gained a strip of the French Congo — at a very high price. Britain was alarmed far more than in 1905: Lloyd George's Mansion House speech warned that Britain would not be treated as of no account, the Royal Navy prepared for action, and Anglo-French naval cooperation deepened.
• Balkan Wars, 1912–13. A Balkan alliance drove the Ottoman Empire almost entirely out of Europe; the victors then fell out and Bulgaria was defeated. The outcome that mattered: Serbia roughly doubled in size and population and emerged confident and ambitious — and Austria-Hungary insisted on creating an independent Albania to deny Serbia the sea, which Serbia deeply resented.

1.3 Britain leaves Splendid Isolation

What the policy meant. Britain avoided permanent peacetime alliances with European powers. It could afford to — the world's largest navy, empire and share of overseas trade, and security that depended on the sea rather than a land frontier. Its European policy was the balance of power: preventing any single state dominating the continent. Four things made isolation unsafe. Imperial overstretch — global rivalries with Russia (Persia, Afghanistan, India), France (Africa — the two came close to war at Fashoda, 1898) and Germany; defending everything against everyone was becoming impossible. The Boer War (1899–1902) — it took a very large force nearly three years to beat a small opponent, and European opinion was almost universally hostile (Wilhelm's Kruger Telegram, 1896 had already made the point): Britain discovered it had no friends. The German navy — the decisive factor (see 1.5): a battle fleet in the North Sea threatened the home waters on which everything depended. And new naval powers — the United States and Japan meant Britain could no longer out-build every possible combination everywhere.

The steps out: the Anglo-Japanese Alliance (1902) — the first break, and a real binding alliance, letting the Royal Navy concentrate closer to home; the Entente Cordiale (1904); the Anglo-Russian Entente (1907); and the military conversations from 1906 (see 1.1). What Britain had and had not committed to: by 1914, two colonial understandings, secret staff talks, and an arrangement leaving France's Channel coast dependent on the Royal Navy — but no treaty obligation to fight for France or Russia. The Cabinet in July 1914 was genuinely divided, which is why the Belgian question mattered so much (see 1.8).

1.4 German ambition: Wilhelm II and Weltpolitik

Wilhelm II became Kaiser in 1888 aged twenty-nine, dismissed Bismarck two years later, and intended to rule personally. Contemporaries found him impulsive, boastful and inconsistent — and under the German constitution he controlled foreign policy, appointed the Chancellor and commanded the armed forces, so his temperament had constitutional consequences. Weltpolitik, announced in the late 1890s, claimed that Germany — now Europe's strongest industrial and military power — deserved a global role to match: colonies, a battle fleet, influence everywhere. Bülow's phrase: “a place in the sun”. The problem was that it had no content. Bismarck's policy had a definable objective (keep France isolated); Weltpolitik had a mood. Which territories did Germany want? Which rival would it fight? Nobody said — so the result was a series of assertive gestures, each of which united other powers against Germany (see 1.2). Germany's actual colonies (South-West and East Africa, Cameroon, Togoland, Pacific islands, Tsingtao) were economically marginal and militarily indefensible, and projects like the Berlin–Baghdad railway alarmed Britain and Russia. Foreign policy also had domestic uses: a conservative elite facing a fast-growing socialist movement used naval and colonial assertion to rally nationalists, industrialists and the middle classes — part of why the policy continued even when it was counter-productive abroad.

1.5 The armaments question and the naval race

Armies grew everywhere. Continental powers used conscription — men served two or three years then passed into the reserves, so peacetime armies of hundreds of thousands could expand to millions within weeks. Germany passed army bills in 1912 and 1913; France extended service to three years in 1913; Russia adopted its “Great Programme” in 1913–14. Britain was the exception: a small professional army, and the navy. The naval race is the sharpest example. Britain's security rested on the Two-Power Standard (the Royal Navy at least equal to the next two navies combined). From 1898, under Tirpitz, Germany built a battle fleet whose only plausible target was Britain — the “risk theory”: build a fleet Britain could not afford to fight without being left too weak elsewhere, forcing it into concessions or friendship. HMS Dreadnought (1906) changed the terms completely: fast, turbine-driven, all-big-gun — every existing battleship, including Britain's own huge fleet, was obsolete, and the race restarted from level. The 1909 scare (“we want eight and we won't wait”) made Britain lay down eight dreadnoughts instead of four, and from then Britain out-built Germany decisively: by 1914 roughly 29 British dreadnought-type battleships to 17 German (figures vary slightly with counting method — give as approximations). Germany lost the race and had made an enemy in the process — and from about 1912 it effectively conceded, shifting resources back to the army.

War plans became commitments — the most important part of the section. The Schlieffen Plan required defeating France in about six weeks before Russia could fully mobilise — meaning any war with Russia became a war with France (see 1.8). France's Plan XVII committed an immediate offensive into Alsace-Lorraine. Russia's plans committed attacks on both Germany and Austria-Hungary. Every plan depended on railway timetables worked out over years. Mobilisation therefore removed decision time: delaying meant losing the advantage to an enemy who did not delay, and altering a plan once begun was believed impossible — Moltke told the Kaiser in July 1914 the deployment could not be changed. The generals had converted political decisions into engineering problems, and once mobilisation began, the timetables ran faster than the diplomats could talk.

1.6 Nationalism in the Balkans

Why the Balkans were unstable. The Ottoman Empire had ruled south-eastern Europe for centuries and was retreating; as it withdrew, new states emerged — Greece, Serbia, Romania, Bulgaria, Montenegro, eventually Albania — and the territory left behind was contested by the new states, by Austria-Hungary and by Russia. Contemporaries called the region the “powder keg of Europe”. Serbia's ambition: fully independent from 1878, and after a violent change of dynasty in 1903 assertively nationalist, seeking a South Slav state uniting Serbs, Croats and Slovenes — many of whom lived inside Austria-Hungary. The Balkan Wars roughly doubled its size and left it confident and ambitious. Austria-Hungary's fear is what made this existential: a multi-national empire — Germans, Hungarians, Czechs, Slovaks, Poles, Romanians, Croats, Slovenes, Serbs, Italians — in which the two dominant nationalities were a minority. A successful Serbia attracting the empire's South Slavs threatened not a border but the empire's existence: if the South Slavs left, the Czechs, Poles and Romanians would follow. That is why Vienna's response to Serbia was always disproportionate to Serbia's size. Russia claimed the role of protector of the Slavs (Pan-Slavism) and, having backed down in 1909, could not credibly do so again.

The Black Hand (formally Unification or Death, founded 1911) was a secret organisation of Serbian nationalists including army officers, led by Colonel Dragutin Dimitrijević (“Apis”) — head of Serbian military intelligence. It trained and armed the group that carried out the Sarajevo assassination. Serbian government responsibility is genuinely uncertain: the government was not the Black Hand and was in some respects its rival; the prime minister appears to have had some warning and gave a vague, ineffective indication to Vienna. Whether Belgrade knew enough to stop the plot is disputed — say so rather than asserting Serbian government guilt.

1.7 The July Crisis

Sarajevo, 28 June 1914. Franz Ferdinand, heir to the Austro-Hungarian throne, visited Sarajevo with his wife Sophie — on St Vitus' Day, the anniversary of a Serbian defeat in 1389 and a date of intense national significance. A Black Hand-armed group waited along the announced route. A bomb thrown that morning bounced off the car; the visit continued; later, the Archduke's driver took a wrong turning, stopped, and began to reverse — directly in front of Gavrilo Princip, who shot the Archduke and his wife at close range. The element of chance is real: without the wrong turning the assassination probably fails. But a failed assassination does not remove the structural conflict — chance explains the timing, not the war.

1.8 Why it did not stay local: the Schlieffen Plan, Belgium and Britain

The problem the plan solved. After 1894 Germany faced a possible war against France and Russia simultaneously — and could not win a long war on two fronts, so it had to defeat one enemy quickly. The choice was made by speed: Russia was expected to take about six weeks to mobilise fully (size, poor railways), so France had to be beaten inside that window. The plan — devised by Schlieffen (Chief of Staff to 1906), modified by Moltke the Younger: a small force holds the east; the great mass of the army attacks in the west, wheeling through Belgium to avoid the fortified Franco-German frontier, sweeping west and south of Paris, and encircling the French armies from behind — in roughly six weeks. Why Belgium: the Franco-German border was short, mountainous and heavily fortified; Belgium offered flat country, good roads and railways. But Belgian neutrality had been guaranteed by the great powers — including Prussia — in the Treaty of London, 1839, the document the German Chancellor reportedly dismissed as “a scrap of paper”.

How the plan escalated the crisis — state it in exactly these four steps:

1. Russia mobilised on 30 July, in a dispute about Serbia.
2. The German plan had no option for a war against Russia alone. Mobilisation meant executing the plan — and the plan began with an attack in the west.
3. Therefore Germany declared war on France, which had done nothing, and demanded passage through Belgium, which had done nothing.
4. The invasion of Belgium brought in Britain.

The British decision. The Cabinet was divided; two ministers resigned; Britain had no treaty obligation to France. Three considerations decided it: Belgium — the 1839 treaty gave a clear, legal, morally comprehensible reason, and the German ultimatum to Belgium (2 August) and invasion (4 August) unified opinion as nothing else could; the balance of power — a Germany that defeated France and Russia would dominate Europe and the Channel coast; and the naval obligation to France — the French Channel coast was undefended because of an arrangement made with Britain. Which was decisive is disputed. Belgium was the stated reason and carried Parliament and the public; the balance of power was the underlying interest. The honest position: Belgium supplied the justification for a decision that would probably have been taken anyway — and saying so is a stronger answer than choosing one.

The factor hierarchy for the causes of the war

Chapter 2 — Stalemate, 1914–1917

Everyone expected a short war. Within four months the Western Front had frozen into a line of trenches from the Channel to Switzerland, and it barely moved for three years. This chapter explains why — and the explanation is not that the generals were stupid. It is that the technology of 1914 favoured defence overwhelmingly, and the means of restoring movement had to be invented, at enormous cost, while the war was going on.

2.1 The plan that failed: the Marne and the making of the trench line

German forces entered Belgium on 4 August 1914, on a plan that required reaching a position west of Paris within about six weeks. Why it failed — six reasons, in order:

1. Belgian resistance. The fortresses at Liège held for over a week; the Belgians flooded ground and destroyed railways and bridges. Days of delay — but in a six-week timetable, days were the currency.
2. Russian speed. Russia invaded East Prussia within about a fortnight. Moltke transferred two army corps from the right wing to the east — where they arrived too late for Tannenberg. He had weakened the decisive wing to reinforce a front that was winning without them.
3. Moltke's earlier modifications. Schlieffen's conception had the right wing overwhelmingly strong; Moltke strengthened the left in Alsace-Lorraine instead, leaving fewer men for the wheel that had to encircle Paris.
4. Logistics — the underrated reason. Armies moved at the speed of marching men and horse-drawn supply; railways ended where the Belgians had destroyed them. By early September the German right wing was exhausted and outrunning its supplies — a physical constraint no plan could remove.
5. The British Expeditionary Force — around 100,000 men, small but professional; its delaying actions at Mons and Le Cateau cost the Germans time.
6. The turn. Facing supply problems and a gap opening in his line, Kluck turned east of Paris rather than west — shortening his march but exposing his flank and abandoning the encirclement the plan required.

The Battle of the Marne, 5–12 September 1914. French forces under Joffre, with the BEF, counter-attacked into the gap between the German First and Second Armies — Gallieni, military governor of Paris, famously sent troops forward in Paris taxis (militarily minor, symbolically enormous). The Germans, with no reserves left, withdrew to the River Aisne and dug in on high ground. The Schlieffen Plan had failed; Moltke was replaced within days. The Race to the Sea followed — not a race but a series of failed outflanking attempts, each extending the line northwards until it reached the Channel and there was nothing left to outflank. First Ypres (October–November) halted the last German attempt and destroyed much of the original BEF. By late November 1914 a continuous trench line ran roughly 700 km from the North Sea to the Swiss frontier (length varies with measurement).

2.2 Living and fighting in the trenches

The trench system — a system, not a ditch. Usually three or more lines deep: the front (fire) trench with its fire step and sandbag parapet; a support trench and a reserve trench behind it, so a lost front line could be counter-attacked; communication trenches running back at right angles; a zigzag (traverse) pattern so no shell burst or intruder could sweep a straight length; dugouts for shelter — the German ones on the Somme famously deep and concrete-lined, able to survive a week of bombardment (directly relevant to 1 July 1916, see 2.3); belts of barbed wire in front; and no man's land between the lines, from a few dozen metres to several hundred. German trenches were generally better — for a strategic reason, not a cultural one: Germany held captured ground it intended to keep, so it built for permanence on high ground; the Allies, intending to attack, built lines they hoped to leave.

Daily life. Units rotated between front line, support, reserve and rest — perhaps a week at a time in the front line, though it varied greatly. Stand-to at dawn and dusk (when attack was most likely); repair and wiring at night; long boredom punctuated by sudden danger. The conditions: mud and water (especially in Flanders, where the water table is high and shelling destroyed the drainage); trench foot (prolonged immersion in cold water, could lead to amputation — whale oil and dry socks prescribed against it); lice, universal, spreading trench fever; rats in enormous numbers; cold, late rations — bully beef, hard biscuit, tinned jam, tea; and shellfire, the chief cause of casualties and the source of what was then called shell shock and is now understood as psychological injury.

The weapons that produced deadlock — each a defensive advantage:

• The machine gun. One well-sited gun with a team of two or three could fire hundreds of rounds a minute across a fixed arc — its effect greatest against troops advancing in the open.
• Quick-firing artillery. Modern recoil mechanisms allowed rapid, accurate fire. Artillery caused the majority of casualties in this war — commonly estimated at around two thirds (estimates vary by front and source).
• Barbed wire. Cheap, quick to lay, lethal with machine guns — it stopped attackers in the open at exactly the point where they could be shot.
• Magazine rifles in the hands of trained infantry — and the spade: not a weapon, but the reason all the above could be survived. Men who dug were far harder to kill.

The tactical answers attempted — and the limitation of each:

• Longer, heavier bombardment — meant to destroy wire and defenders first. In practice it warned the enemy where the attack would come, churned the ground into an obstacle, often failed to cut wire, and (as on the Somme) failed to destroy deep dugouts.
• The creeping barrage — shells moving forward in timed lifts just ahead of the infantry, keeping defenders in their dugouts until the attackers arrived. Developed from 1916, increasingly effective — but demanding accurate guns, accurate maps and disciplined infantry.
• Poison gas — first used on a large scale by Germany at Second Ypres, April 1915 (chlorine); then phosgene, and from 1917 mustard gas. It rarely produced a breakthrough: it depended on wind, could blow back, and respirators appeared quickly. Its main achievement was to make the battlefield more miserable rather than more decisive.
• Mining — tunnelling under enemy lines and detonating explosives, most spectacularly at Messines, June 1917, where nineteen mines fired simultaneously were reportedly heard in London. Effective locally; impossible to repeat quickly.
• Tanks — first used on the Somme, 15 September 1916, in small numbers: slow, unreliable, easily ditched — but they crossed wire and trenches and were immune to rifle and machine-gun fire. Cambrai, November 1917 showed what massed tanks with surprise could do — and that gains could not be held without infantry and reserves.
• Aircraft — above all for reconnaissance and artillery spotting, their most important role throughout; aerial photography transformed artillery accuracy, which is why air superiority mattered.

2.3 Attrition: Verdun, the Somme and Passchendaele

What attrition means: winning by inflicting more losses than the enemy can replace, rather than by capturing ground — a strategy for a war in which breakthrough is impossible and one side has more men and industry than the other. It is also, in practice, a decision to accept enormous casualties of your own in order to impose greater ones. The specification asks for each battle's reasons, events and significance — use that three-part structure in a “write an account” answer.

Verdun, February–December 1916

Reasons: Falkenhayn chose Verdun for what it meant, not what it was worth — a fortress city of great symbolic importance that France would defend at any cost. His stated aim (in a memorandum whose authenticity has been questioned, though its logic matches German conduct) was to “bleed France white”: not to take Verdun but to destroy the French army defending it. Events: the offensive opened 21 February 1916 with an enormous bombardment; Fort Douaumont fell within days, almost without a fight. Pétain took command — “Ils ne passeront pas” (“they shall not pass”) — and organised the defence around a single supply road, the Voie Sacrée, rotating French units through the battle so that most of the French army passed through Verdun. The fighting lasted about ten months over a small area. Significance: Verdun held — but combined French and German casualties are commonly estimated at roughly 700,000–976,000, and totals vary substantially between sources. Crucially, German losses were nearly as heavy as French, which defeated the purpose: a battle designed to bleed France white bled Germany almost equally. Falkenhayn was replaced in August 1916; Verdun became the central French memory of the war; and it forced the British to launch the Somme earlier and more ambitiously than planned.

The Somme, 1 July – 18 November 1916

Reasons, in order: planned as a joint Anglo-French offensive where the two armies met; Verdun changed it — the French contribution shrank and the timing became urgent, to draw German forces away; and it was the first use of Kitchener's New Armies — the volunteers of 1914–15, including the Pals battalions raised from single towns and workplaces. Events: a bombardment of about a week and a half fired over 1.5 million shells — and largely failed: many were duds, many were shrapnel that could not cut wire, and the German dugouts were too deep. On 1 July 1916 the infantry advanced: around 57,000 British casualties in the single day, around 19,000 killed — the worst day in British military history. Some Pals battalions meant a single town lost most of its young men in one morning. The battle continued four and a half months; tanks were first used on 15 September; the total advance was a handful of kilometres. Significance: total casualties are commonly estimated at over a million on all sides — British around 400,000, French around 200,000, German 400,000–600,000; all estimates, and the German figure in particular is disputed. The Somme relieved Verdun, inflicted losses Germany could replace less easily than the Allies — and, the point most often missed, it is where the British Army learned: the creeping barrage, counter-battery fire, platoon tactics and air cooperation all developed out of its failures (see 3.4). The German withdrawal to the prepared Hindenburg Line in early 1917 is itself an admission of the damage done.

Passchendaele (Third Ypres), July–November 1917

Reasons: Haig wanted to break out of the Ypres salient, reach the Belgian coast and capture the ports from which German submarines operated (see 2.6) — and pressure had to be kept on Germany because the French army had mutinied after the failed Nivelle Offensive and Russia was collapsing (see 3.1). Events: after the genuine success at Messines (June 1917), the main offensive opened 31 July — into the wettest weather in the region for years, on ground whose drainage the bombardment had destroyed. The battlefield became a swamp in which shell holes drowned men and mules. Passchendaele village was finally taken in November. Significance: around five miles gained; British and Commonwealth losses commonly estimated at 240,000–275,000, German comparable — with a wide range in the estimates. No strategic gain; the ground was abandoned in 1918. It is the strongest single piece of evidence for the case against Haig (see 3.6): the mud was visible, the objectives were not achieved, and the decision to continue into November is hard to defend.

2.4 The war on other fronts

• The Eastern Front — roughly 1,600 km, far less densely held, so it stayed a war of movement. Tannenberg (August 1914) and the Masurian Lakes were crushing German victories over invading Russian armies — aided by Russian wireless messages sent uncoded — and made the reputations of Hindenburg and Ludendorff. Russia did better against Austria-Hungary, which repeatedly needed German rescue — the weak point of the Central Powers throughout. The Brusilov Offensive (1916) was Russia's greatest success, inflicting very heavy Austro-Hungarian losses and pulling German divisions east (relieving Verdun) — at a cost in casualties Russia could not sustain, contributing directly to the collapse of 1917 (see 3.1). Russia's real problems were supply: rifles, shells, boots, railways — and a government losing legitimacy.
• Italy — stayed out in 1914 and joined the Allies in 1915, promised Austrian territory. It fought along the Isonzo in the mountains — eleven or twelve battles, enormous casualties, almost no movement. At Caporetto (October 1917) a German-reinforced attack broke the Italian line; the Italians held on the Piave and recovered. The Italian front proves the stalemate was not a peculiarity of Flanders — the same deadlock occurred in the Alps.
• Salonika — an Allied force landed in 1915 to help Serbia, arrived too late, and sat in northern Greece for three years (German propaganda called it their “largest internment camp”). It mattered at the very end: the force finally advanced and Bulgaria surrendered in September 1918 — the first crack in the Central Powers (see 3.4).
• The Middle East — the Ottoman Empire joined Germany in late 1914. In Mesopotamia a British-Indian force was besieged at Kut and surrendered (April 1916) before a larger force took Baghdad in 1917. In Palestine, Allenby took Jerusalem in December 1917 and broke the Ottoman armies in 1918. The Arab Revolt from 1916 — supported by British officers including T. E. Lawrence — tied down Ottoman troops. (Gallipoli belongs to this theatre: see 2.5.)
• Africa and the empires — German colonies fell relatively quickly, except German East Africa, where von Lettow-Vorbeck campaigned until the armistice, tying down far larger Allied forces. African deaths — chiefly from disease and forced labour — were high and are poorly recorded. Britain and France drew troops and labour from their empires on a vast scale — Indian, Canadian, Australian, New Zealand, South African, West Indian and African contingents — which is what made it a world war in more than name.

2.5 Gallipoli

The four aims explain why an apparently eccentric operation was attempted: relieve Russia (which had appealed for a diversion in January 1915); open a supply route through the Black Sea (the Baltic was closed, the northern ports ice-bound — Russia had grain to export and needed munitions); knock the Ottoman Empire out of the war, possibly bringing in the neutral Balkan states; and break the deadlock in the west by going round it — the “Easterner” argument. Churchill, First Lord of the Admiralty, was the campaign's most energetic advocate and pressed for a purely naval operation: ships would force the Dardanelles and threaten Constantinople without troops.

The naval attempt failed first. On 18 March 1915 a major attempt to force the narrows ran into an undetected minefield: three battleships sunk and three badly damaged in a single day, and the naval attack was abandoned. The planning failures that followed are examinable: the naval attempt had destroyed surprise (the Ottomans reinforced the peninsula under German supervision between March and April); intelligence and maps were poor and the terrain far harder than expected; the Ottoman army was underestimated on frankly racial assumptions — it fought extremely well; logistics were improvised over open beaches with no port; and water was the fundamental constraint on a dry peninsula in a Mediterranean summer. The landings (25 April 1915) went in at Cape Helles and — about a mile from the intended beach, beneath steep cliffs — at what became Anzac Cove. At V Beach troops were shot down as they left the landing ships. Within days the attackers were held: Mustafa Kemal moved his troops to the high ground at the critical moment, reportedly telling them he was not ordering them to attack but to die. The campaign became trench warfare within weeks — the same deadlock it was designed to avoid, on worse ground: extreme heat, no shade, flies, near-universal dysentery, then flooding and frostbite in November. Suvla Bay (August 1915) achieved surprise and stalled through hesitant leadership within a day. Hamilton was recalled in October; the evacuation (December 1915 – January 1916) — conducted with elaborate deception and almost no casualties — was the most successful part of the entire campaign. Allied casualties are commonly given as around 250,000 (about 44,000 dead); Ottoman casualties comparable or greater, with around 87,000 dead often cited — all estimates.

2.6 The war at sea

The blockade — Britain's most important naval action was not a battle. From August 1914 the Royal Navy imposed a distant blockade, closing the exits from the North Sea (the Channel, and the Scotland–Norway gap) rather than patrolling near German ports where mines and submarines waited. It was progressively tightened: contraband was extended to include food and fertiliser, neutral shipping was stopped and searched — causing real friction with the United States. Its effect was cumulative and enormous: Germany could not import food, fertiliser or raw materials, and its agriculture — short of labour, horses and nitrates — could not compensate. It was a weapon that worked slowly, invisibly and decisively (its contribution to defeat: see 3.5).

Jutland, 31 May – 1 June 1916 — the only major fleet action of the war: Jellicoe's Grand Fleet (roughly 150 ships) against Scheer's High Seas Fleet (roughly 100). Scheer meant to lure out and destroy part of the British fleet; instead both main fleets met. British battlecruisers suffered catastrophically — HMS Indefatigable, Queen Mary and later Invincible blew up, the result of poor shell-handling and cordite stacked in turrets. Twice Jellicoe “crossed the T”; twice Scheer escaped by simultaneous turn-away into mist. Jellicoe declined to pursue at night, when torpedoes favoured the weaker fleet. The result was ambiguous — and that ambiguity is the examinable point. Britain lost more ships and men (around 14 ships and over 6,000 men, against around 11 and 2,500 — figures vary slightly by counting); Germany claimed a tactical victory. But Britain won strategically, and decisively: the German fleet returned to port and never seriously challenged the Grand Fleet again. The blockade continued unbroken. Jellicoe was, in Churchill's phrase, the only man who could have lost the war in an afternoon — and he did not lose it.

The U-boat campaign. Unable to win on the surface, Germany turned to the one weapon that could threaten Britain's lifeline — Britain imported a very large share of its food. Unrestricted submarine warfare (sinking without warning, including neutrals) was declared in February 1915, then restricted after the Lusitania was sunk in May 1915 — around 1,200 dead including over 100 Americans. In February 1917 Germany resumed it, calculating that Britain could be starved out in about five months — before American forces could arrive in strength. It was a deliberate gamble that accepted American entry as the price (see 3.2). It very nearly worked: April 1917 was the worst month, around 860,000 tons sunk, and Britain was reported to be within weeks of a serious food crisis. Convoys defeated it — a solution administrative rather than technological, and resisted by the Admiralty before it was adopted (merchant ships couldn't keep station; a convoy was a bigger target; escorts weren't available — all wrong). A convoy is harder to find than a single ship (the ocean is mostly empty, and twenty ships together are one target to find instead of twenty); escorts finally had something to defend; and a submarine attacking a convoy had to expose itself. Introduced from May 1917, convoys — with depth charges, hydrophones, mine barrages and aircraft patrols — contained the threat by the end of 1917.

Chapter 3 — Ending the war, 1917–1918

In March 1918 Germany was closer to winning the war than at any time since the Marne. Eight months later it asked for an armistice. This chapter explains that reversal — not a single decisive battle but the convergence of four things: the arrival of American strength, the exhaustion of Germany's best troops, an Allied army that had finally learned how to attack, and a home front that had run out of food.

3.1 Russia leaves the war

Why Russia collapsed. Enormous manpower and inadequate everything else: very heavy casualties; chronic shortages of rifles, shells, boots and food; a railway network that could not supply both army and cities; and a Tsar who, having taken personal command in 1915, attached his own authority to a run of defeats. In February/March 1917 strikes and demonstrations in Petrograd — and the garrison's refusal to fire on the crowds — forced Nicholas II to abdicate. The Provisional Government made the decision that destroyed it: it continued the war, and a failed summer offensive finished it. In October/November 1917 the Bolsheviks under Lenin seized power, promising “Peace, Bread, Land” — and peace came first. (The revolutions' details belong to the Russia unit; what matters here is that by the end of 1917 Russia had a government committed to leaving the war immediately.) An armistice came in December 1917; when the Bolsheviks stalled at the negotiating table, the Germans simply resumed their advance, and the Treaty of Brest-Litovsk was signed on 3 March 1918. The terms were extraordinarily harsh: Russia lost Poland, Finland, the Baltic provinces and Ukraine — roughly a third of its population, a very large share of its industry and coal, and much of its agricultural land (figures are approximations) — plus an indemnity. Remember Brest-Litovsk for a second reason: when Germany later complained that Versailles was uniquely harsh, the terms Germany had imposed on Russia a year earlier were the obvious reply.

The consequences for German strategy — the specification's actual question. Germany could at last fight on one front: around fifty divisions (approximate) moved west over the winter of 1917–18, giving Germany numerical superiority in the west for the first time since 1914. But the advantage was temporary, and Ludendorff knew it — three clocks were running: American troops were arriving (see 3.2); the blockade was strangling the home front, and another winter might be unendurable (see 3.5); and Germany's allies were failing (see 2.4). And Germany did not get all its eastern troops: around a million men stayed east to occupy and exploit the vast new territories, extracting grain that never arrived in the quantities expected. Germany's victory in the east consumed part of the army it needed in the west — one of the sharpest ironies of the war. Ludendorff's conclusion: Germany had a window of a few months, and must win the war inside it. That decision produces the Spring Offensive (see 3.3).

3.2 America enters the war

Why the United States had stayed out: Wilson was re-elected in 1916 on having kept America out; opinion was genuinely divided — large German- and Irish-descended populations with no wish to fight for Britain, a strong tradition against European entanglements, and a widespread view that this was a European quarrel about empires. Why it came in — five reasons, in order:

1. Unrestricted submarine warfare — the decisive cause. Germany resumed it in February 1917 knowing it would probably bring America in, and gambling Britain would collapse first (see 2.6). American ships were sunk and American lives lost.
2. The Lusitania's legacy. Sunk May 1915, around 1,200 dead including over 100 Americans. It did not bring America in — but it shaped opinion permanently, which is why the 1917 resumption produced such a rapid reaction.
3. The Zimmermann Telegram. In January 1917 the German Foreign Secretary proposed to Mexico that, if America entered the war, Mexico should join Germany and recover Texas, New Mexico and Arizona. British intelligence intercepted and decoded it; it was published in March 1917 — and Zimmermann publicly confirmed it was genuine. Coming weeks after the submarine declaration, it converted a grievance into an outrage.
4. Economic ties. American trade with the Allies had grown enormously while the blockade cut off trade with Germany, and American banks had lent very large sums to Britain and France. State this without overstating it: it is not why Wilson asked for war, but it is why the American economy was already committed to one side.
5. Ideology. Wilson framed the war as making the world “safe for democracy” — and the fall of the Tsar in March 1917 removed the awkwardness of allying with an autocracy.

War was declared on 6 April 1917 — and the United States entered as an “Associated Power”, not an ally, keeping its freedom of action (which mattered for the peace afterwards). The impact, measured honestly: in 1917 it was slight — the army was tiny and had to be raised, trained, equipped and shipped across a submarine-infested ocean; very few Americans fought before 1918. In 1918 it was decisive: around two million reached France, arriving at around 250,000 a month by summer, in divisions roughly double the size of European ones; they fought at Belleau Wood and Château-Thierry and mounted their own offensives at Saint-Mihiel and the Meuse-Argonne (Pershing insisting on an independent American army). Materially American food, steel, oil, munitions, shipping and loans sustained the Allied effort throughout.

3.3 The German Spring Offensive

Ludendorff's position by early 1918: temporary superiority in the west (see 3.1), Americans coming (see 3.2), the home front starving (see 3.5). Germany must win in the spring of 1918 or lose the war. The new tactics — developed in the east and at Riga and Caporetto, associated with General von Hutier: a short, intense, precisely targeted bombardment (hours, not a week — gas and high explosive aimed at headquarters, artillery and communications, warning nobody and preserving the ground); predicted fire (guns calibrated to fire accurately without ranging shots); stormtroopers — selected, specially trained assault infantry with grenades, light machine guns, flamethrowers and mortars; infiltration — advancing in small groups, bypassing strong points and pushing deep into the rear, leaving following waves to mop up; and decentralised command — junior officers exploiting success wherever it appeared.

Operation Michael (21 March 1918) fell on the British Fifth Army in fog, after a bombardment of a few hours. The results were spectacular by Western Front standards: the line broke, and German forces advanced up to around 65 km in some sectors — more than any advance since 1914. There was a real crisis: Haig issued his “backs to the wall” order in April. One consequence was organisational and lasting: the emergency produced, at the Doullens Conference (March 1918), the appointment of Foch as coordinator and soon Supreme Commander of the Allied armies — the first unified Allied command of the war. Four further offensives followed between April and July, each achieving initial success and then stalling; by July the Germans were again on the Marne, within artillery range of Paris. Why the offensives failed — five compounding reasons: no strategic objective (Ludendorff's stated intention was to punch a hole and see what happened — an operation without an objective cannot know when it has succeeded, so the advances went where success was easiest rather than where it mattered); the old logistics problem (stormtroopers moved fast; artillery, ammunition and food still moved at the speed of horses over four-year-old battlefields — exactly as in 1914); salients (each advance created a bulge exposed on three sides and needing more men to hold than the straight line it replaced); the stormtroopers died (the assault divisions had been formed by stripping the best men from the whole army; their heavy casualties could not be replaced — Germany destroyed its own offensive capability in the act of using it); and hunger (advancing troops repeatedly stopped to loot Allied supply dumps, astonished by the food available to men they had been told were starving — anecdotal, widely reported, and evidence of the blockade's effect on morale). German casualties in the spring offensives are commonly estimated at around a million, with comparable Allied losses (all estimates) — but the Allies had American manpower arriving at a quarter of a million a month, and Germany had nobody.

3.4 The Hundred Days

The Battle of Amiens (8 August 1918) opened the Allied counter-offensive — British, Australian, Canadian and French forces, using everything the war had taught, all at once: no preliminary bombardment (surprise preserved by predicted artillery fire — guns calibrated and surveyed to hit map coordinates without ranging shots, with sound ranging and flash spotting locating German batteries in advance); counter-battery fire silencing the German artillery in the opening minutes; a creeping barrage ahead of the infantry; over 500 tanks, including faster Whippets for exploitation; aircraft attacking, observing — and flying low along the front to mask the noise of tanks moving up; infantry fighting with their own light machine guns, mortars and rifle grenades rather than advancing in lines; and deception concealing the concentration. The advance covered several miles on the first day, and large numbers of German prisoners surrendered readily. Ludendorff called it “the black day of the German Army” — not because of the ground lost but because German troops had surrendered in numbers and shouted at reinforcements that they were prolonging the war.

The method that followed. Rather than continuing at Amiens until the attack bogged down — the mistake of every previous offensive — Foch and Haig switched the point of attack: a sector was attacked until resistance hardened, then the effort moved elsewhere while the Germans were still redeploying. Successive blows fell along the front, never letting the defenders concentrate — the Hundred Days, from Amiens to the armistice. The Germans withdrew to the Hindenburg Line — deep, heavily wired, built around the St Quentin canal — and from 29 September 1918 the Allies broke through it with the same combined-arms method. Meanwhile Germany's allies collapsed: Bulgaria surrendered on 30 September (after the Salonika force finally advanced), the Ottoman Empire on 30 October (after Allenby's Palestine victories), and Austria-Hungary on 3 November, disintegrating as its nationalities declared independence. Germany was now alone, with an exhausted army, a collapsing home front and no allies.

3.5 Germany surrenders: blockade, abdication and armistice

The blockade's effect — slowly, then all at once. Germany had imported a substantial share of its food and almost all its nitrates — needed for both fertiliser and explosives. Cut off from both, it chose the guns over the soil; agriculture also lost labour and horses to the army, so domestic production fell as imports stopped. Rationing began early and tightened; the winter of 1916–17 became the “turnip winter” after the potato crop failed. Civilian deaths attributable to the blockade are contested — contemporary German official estimates were very high, historians have argued for lower figures, and the 1918 influenza pandemic complicates everything: present it as a range of several hundred thousand and say it is disputed. The effects were unevenly spread — a black market flourished, the rich ate, and the sense of injustice was politically corrosive. The military effect mattered as much: shortages of rubber, oil, cotton, metals and fats; Ersatz substitutes for everything; German soldiers in 1918 worse fed and worse equipped than their enemies — which is why the looting of Allied supply dumps during the Spring Offensive was so damaging to morale.

The collapse, in sequence — and the sequence is the point. By late September 1918 the position was hopeless: the Hindenburg Line broken, Bulgaria out, the army retreating. On 29 September 1918 Ludendorff told the government that an armistice must be sought immediately — the demand came from the army high command, not from politicians or the public, and while German troops still stood on French and Belgian soil. Ludendorff also recommended a government based on the Reichstag — partly for better terms from Wilson, partly (as later became clear) so that civilians would carry the responsibility for defeat: the origin of the later “stabbed in the back” claim. In late October the naval command ordered the High Seas Fleet out for a final battle; to crews who had sat in harbour since Jutland this was a pointless death sentence, and on 29 October sailors at Wilhelmshaven and then Kiel refused orders — the mutiny spreading through the ports into the cities. With unrest spreading and the army's support gone, the Kaiser's abdication was announced on 9 November, and the Armistice was signed on 11 November 1918 in a railway carriage at Compiègne — by a civilian delegation, on the army's insistence — effective at 11 a.m. Its terms were designed to make resuming the war impossible: evacuation of all occupied territory and Alsace-Lorraine; Allied occupation of the Rhineland; surrender of enormous quantities of equipment and of the fleet and all submarines; annulment of Brest-Litovsk; and the blockade to continue until a peace treaty was signed — which it did, into 1919, causing lasting bitterness. An armistice is not a peace treaty — it stopped the fighting; the settlement came separately.

3.6 Generalship in the balance: Haig and Foch

Douglas Haig commanded the BEF from December 1915 to the end of the war: the Somme, Passchendaele, the Spring Offensive crisis, the Hundred Days. The two cases:

Ferdinand Foch — appointed coordinator of the Allied armies at Doullens (March 1918), then Supreme Commander: the first unified Allied command of the war. His contributions: unity of command — until 1918 the British, French, Belgian and American armies operated by agreement between allies who did not always agree; Foch could direct reserves across national boundaries, which is what stabilised the front during the Spring Offensive; the strategy of the Hundred Days — successive attacks at different points, denying the Germans time to concentrate, was his conception; and persistence — his reported message from the Marne in 1914 (“my centre is giving way, my right is falling back: I shall attack”) captures a temperament that mattered in March 1918, when the alternative was despair. His limits: he commanded by persuasion as much as authority — national commanders retained the right of appeal to their governments, and his relations with Haig and Pershing were often difficult.

Pulling it together, 1894–1918

Change over time

Factor hierarchies for the main-reason essay

Question 4 names a “main reason” and asks how far you agree. These are ranked argument frames for the three outcomes this option asks about — state your criterion, apply it, and hold it.

Outcome A — Why war broke out in 1914

• On sufficiency → Balkan nationalism. Without an irreconcilable Austro-Serbian conflict there is no crisis to escalate.
• On enabling power → German policy. It repeatedly converted manageable situations into confrontations and removed the option of a limited war.
• On counterfactual → the war plans. Remove the Schlieffen Plan and the 1914 crisis produces an eastern European war, not a world war.

Outcome B — Why the stalemate lasted

Suggested criterion: enabling power for the technology, and counterfactual for the exploitation problem — ask what would have had to exist in 1916 for a breakthrough to become a victory, and note that the answer is the combination that appeared in 1918.

Outcome C — Why Germany was defeated

• On sufficiency → American entry. Given time, no German strategy could match Allied resources afterwards.
• On enabling power → the blockade. It removed Germany's capacity to sustain a long war — the war it was forced to fight after the Marne.
• On timing → the Spring Offensive. It is why defeat came in November 1918 rather than 1919: it destroyed the German army's offensive capacity in four months.

Source workbench

Questions 1 and 2 are worth twelve of this section's forty marks and are pure source work. Two principles govern everything below. A limitation is not uselessness — a censored photograph is poor evidence of what a battlefield looked like and excellent evidence of what the public was permitted to see; say what a source is useful for. And match the source to the enquiry — each row ends with the enquiry for which that type is genuinely valuable.

Quick self-test

Cover the answers and check yourself. Each answer names the section where the full evidence lives.