Why did the Schlieffen Plan fail?

Germany faced the nightmare of a war on two fronts — France in the west, Russia in the east. The Schlieffen Plan was the German answer: knock France out fast with a huge sweep through Belgium, then turn the army east before Russia could fully mobilise.

• Germany declared war on France on 3 August 1914 and invaded neutral Belgium on 4 August 1914. Britain, a guarantor of Belgian neutrality, declared war on Germany later the same day.
• Belgian resistance at the Liège forts slowed the advance, and the British Expeditionary Force (BEF) — small but highly trained — fought a delaying action at the Battle of Mons (23 August 1914).
• Russia mobilised faster than expected. Two German corps were pulled away from the west and sent east, weakening the sweep at the crucial moment.
• The German right wing wheeled short of Paris and exposed its flank. At the Battle of the Marne (September 1914) the French and BEF counter-attacked and the Germans fell back to the River Aisne.

Exam framing: the plan failed for a mixture of reasons — an over-ambitious timetable, Belgian and British resistance, the speed of Russian mobilisation, and the German decision to divert troops. A strong answer weighs them, rather than listing them.

Why did a defensive war emerge by the end of 1914?

After the Marne, both sides tried to outflank each other northwards — the race to the sea. It ended at the Channel. At the First Battle of Ypres (October–November 1914) the BEF held the line, but at terrible cost.

Why did defence beat attack? Because the technology of 1914 favoured the defender: machine guns, quick-firing artillery, barbed wire and entrenchments could shred an advancing infantry attack, while there was no fast way to move reserves forward across the shell-torn ground. The result was a war of attrition — grinding the enemy down rather than out-manoeuvring him.

Why did the plan collapse?

What was living and fighting in the trenches like?

Trench systems were built in depth: a front line, a support trench behind it and a reserve trench further back, linked by communication trenches. Between the two sides lay no man’s land, strung with barbed wire.

• Routine, not constant combat: men rotated between front line, support, reserve and rest. Days were dominated by sentry duty, repairs, carrying parties and waiting.
• Conditions: mud and standing water caused trench foot; lice caused “trench fever”; rats and rotting corpses were everywhere. Dysentery spread easily.
• Danger: most casualties came from artillery, not rifle fire. Snipers, gas alerts and raids kept men on edge; shell shock was widespread and poorly understood.

Careful with generalisations: conditions varied enormously by sector and season. A quiet stretch of line in 1915 was nothing like the Somme in July 1916 — a good answer says so.

How important were new methods of warfare?

• Machine guns — able to fire hundreds of rounds a minute; the backbone of trench defence.
• Artillery — the biggest killer of the war. Huge preliminary bombardments were meant to cut wire and destroy trenches; later the creeping barrage moved just ahead of advancing infantry.
• Gas — chlorine was first used on a large scale by the Germans at the Second Battle of Ypres in April 1915. Phosgene and, from 1917, mustard gas followed. Gas terrified soldiers, but respirators soon limited its battlefield value.
• Tanks — first used by the British at Flers-Courcelette on 15 September 1916, during the Somme. Early tanks broke down constantly. Massed properly at Cambrai (November 1917) they showed real promise.
• Aircraft — began as reconnaissance and artillery spotting, then developed into fighters and bombers as each side tried to blind the other.

Judgement: no single weapon broke the stalemate. What eventually did was combined arms — artillery, infantry, tanks and aircraft working together, as in the Allied advance of 1918.

The Battles of Verdun and the Somme (1916)

Verdun began on 21 February 1916. The German commander Falkenhayn attacked the fortress city that France, for reasons of national pride, would not abandon — the aim was to bleed the French army white. The battle ground on until December 1916 and cost both sides enormous casualties. France held.

The Somme opened on 1 July 1916, partly to relieve the pressure on Verdun. A week-long British bombardment failed to cut much of the German wire or destroy deep dugouts. On the first day the British Army suffered around 57,000 casualties, of whom roughly 19,000 were killed — the bloodiest day in its history. The offensive continued until 18 November 1916 and advanced only a few miles.

Was Haig a butcher? Critics point to the rigid plans, the belief in the bombardment and the casualties for tiny gains. Defenders argue he was fighting a coalition war he could not walk away from, that the Somme wore down the German army and that the British learned the tactics (creeping barrage, combined arms) that won in 1918. Cambridge wants a balanced judgement, not a slogan.

Name the plan

Troops from the British Empire on the Western Front

Britain did not fight alone: it drew on the manpower of a global empire. The syllabus sets two case studies.

• Indian troops. The Indian Corps arrived in France in 1914 and held sections of the line through the first winter — in cold, wet conditions utterly unlike home, with equipment and rifles that at first did not match the British ones. Indian divisions attacked at Neuve Chapelle in March 1915. The infantry divisions were withdrawn from France at the end of 1915 and sent to the Middle East, though Indian cavalry stayed.
• Canadian troops. Canadians faced the first large German gas attack at Second Ypres in April 1915 and held the line. The Canadian Corps went on to take Vimy Ridge in April 1917 — a set-piece attack, meticulously rehearsed, that became a founding moment of Canadian national identity.

Significance: empire troops supplied manpower Britain could not raise alone, but they were often given the hardest tasks and were not treated as equals. Their contribution fed post-war demands for greater self-government.

Africa, Japan and the Arab Revolt

• German East Africa. The German commander von Lettow-Vorbeck fought a brilliant guerrilla campaign with a small force of German officers and African askari soldiers. He tied down far larger Allied armies and had still not been defeated when the war ended in November 1918. African carriers and civilians suffered appallingly from disease and forced labour.
• German South West Africa. South African forces under Louis Botha invaded and forced the German colony to surrender in July 1915 — a swift, successful campaign, though it provoked a rebellion by pro-German Afrikaners at home.
• Japan. Japan entered the war as Britain’s ally and besieged the German naval base at Tsingtao (Qingdao), which fell in November 1914. Japan also seized German islands in the Pacific and, crucially, used its navy to secure the sea lanes, escorting convoys and freeing British warships for European waters.
• The Arab Revolt. Beginning in June 1916, Sharif Hussein of Mecca and his sons — with British support and the officer T. E. Lawrence — rose against Ottoman rule. Arab forces took Aqaba in July 1917 and raided the Hejaz railway, tying down Ottoman troops and protecting the flank of the British advance that reached Damascus in October 1918.

Japan’s contribution

Who won the war at sea?

The Battle of Jutland (31 May – 1 June 1916) was the only full-scale clash of the British Grand Fleet (Jellicoe) and the German High Seas Fleet (Scheer). Britain lost more ships and more men — yet the German fleet retreated to port and never seriously challenged again. Strategically, Britain kept command of the sea and the blockade held.

• The blockade slowly strangled German food and raw material supplies — a decisive, unglamorous weapon.
• U-boats were Germany’s answer. The liner Lusitania was sunk on 7 May 1915, killing more than a thousand people including Americans, and outraging US opinion.
• Germany resumed unrestricted submarine warfare in February 1917, gambling that it could starve Britain out before the USA could act.
• Britain replied with the convoy system from 1917: merchant ships sailed in escorted groups. Shipping losses fell sharply and the U-boat gamble failed.

Exam line: Jutland was a tactical draw (arguably a German tactical success) but a British strategic victory — the fleet that stays in harbour does not control the sea.

Why did the Gallipoli campaign of 1915 fail?

The idea was to knock the Ottoman Empire out of the war, open a supply route to Russia through the Dardanelles and break the deadlock. A naval attack in February–March 1915 failed against mines and shore guns. Landings followed on 25 April 1915 at Cape Helles and at Anzac Cove, with a further landing at Suvla Bay in August 1915.

• Poor planning and intelligence — maps were bad, the terrain was steep and the objectives vague.
• Loss of surprise — the naval attack had warned the Ottomans, who reinforced the peninsula.
• Determined Ottoman defence, including the counter-attacks organised by Mustafa Kemal.
• Disease, heat and flies wrecked the health of the troops; another trench stalemate set in.

The Allies evacuated between December 1915 and January 1916 — ironically the best-executed part of the whole campaign, carried out with almost no casualties.

The Eastern Front and the impact on civilians

The Eastern Front was a war of movement over vast distances. Russia invaded East Prussia and was crushed at Tannenberg (August 1914) and the Masurian Lakes (September 1914). The Brusilov Offensive of June 1916 was Russia’s greatest success and badly hurt Austria-Hungary, but at a cost Russia could not bear. Defeat, hunger and misrule brought revolution in 1917, and the new Bolshevik government signed the Treaty of Brest-Litovsk on 3 March 1918, taking Russia out of the war and freeing German divisions for the west.

Civilians were now part of the war effort — this was total war:

• Britain: the Defence of the Realm Act (DORA, 1914) gave the government sweeping powers over industry, censorship and daily life; rationing was introduced in 1918; women moved into munitions and other war work in huge numbers.
• Germany: the British blockade caused severe shortages — the winter of 1916–17 became known as the turnip winter because turnips replaced potatoes and bread.
• Air raids: Zeppelin and later Gotha bomber raids on British towns brought the war to the home front and fuelled anti-German feeling.
• Propaganda and censorship were used everywhere to keep up morale and recruitment.

Which part of the war?

Tap a card, then tap the column it belongs in.

What was the importance of America’s entry?

The USA declared war on Germany on 6 April 1917. Two things pushed it in: unrestricted submarine warfare (American ships and lives were being lost) and the Zimmermann Telegram, a German offer to Mexico of American territory if it joined a war against the USA, intercepted by Britain and published in March 1917.

• Manpower: American troops arrived slowly at first, but by mid-1918 they were landing in huge numbers — fresh men against an exhausted German army.
• Economic weight: American money, food, steel and shipping propped up the Allied war effort.
• Morale: Allied spirits rose; German commanders knew the clock was now running against them.

Cause and effect: American entry did not win the war overnight — it made a German victory in 1918 a race against time. That is exactly why Ludendorff gambled on a spring offensive.

Why was the German offensive of 1918 unsuccessful?

With Russia out of the war, Germany moved divisions west and attacked on 21 March 1918 (the Spring Offensive, beginning with Operation Michael). Using stormtroopers and short, intense bombardments, the Germans broke through and advanced further than anyone had since 1914.

• But they outran their supplies; hungry troops stopped to loot Allied stores.
• They took ground, not war-winning objectives, and created a long, exposed salient that was hard to defend.
• Casualties were irreplaceable — Germany had no reserves left, while American troops kept arriving.
• The Allies, now under a unified command (Foch), absorbed the blow and counter-attacked at Amiens on 8 August 1918 — Ludendorff called it “the black day of the German army”. The Hundred Days advance rolled the Germans back.

Why did Germany ask for an armistice?

• Military defeat in the field — the Hundred Days advance was pushing the German army back and its commanders knew the war was lost.
• Germany’s allies collapsed — Bulgaria surrendered in September 1918, the Ottoman Empire in October 1918, Austria-Hungary in early November 1918.
• The blockade had left civilians hungry and war-weary; strikes and unrest spread.
• Revolution. Ordered to sail out for a last battle in late October 1918, sailors mutinied — at Wilhelmshaven and then at Kiel (early November 1918). Workers’ and soldiers’ councils sprang up across Germany.
• On 9 November 1918 the Kaiser abdicated and a republic was declared. The new government signed the Armistice on 11 November 1918; the guns fell silent at 11 a.m.

Important: Germany was not invaded in 1918. Its army was beaten in the field and its home front had cracked — but because no enemy troops stood on German soil, some Germans later swallowed the myth that the army had been “stabbed in the back”.

Jutland’s real result

Cause → consequence

Tap a cause on the left, then its consequence on the right.

Name the battle

Build the timeline

Tap the events in order, earliest first.

1918: the turning point

Source skills for Paper 2

The essentials to remember

You have covered all four key questions of Depth Study A. Press Finish to see your score.