Four years. Three months. A line of mud and wire from the North Sea to the Swiss border. This is how it happened — and what it cost.
In the summer of 1914 Europe's great powers were bound together by alliances, rivalries and rigid war plans. When a young nationalist shot Archduke Franz Ferdinand in Sarajevo, the chain reaction took barely five weeks to pull the continent into war.
Soldiers marched off cheering, promised they would be home before the leaves fell — or at the latest by Christmas. Instead, modern firepower met old-fashioned tactics, and the armies of the Western Front did the only thing that kept them alive: they dug in.
By the winter of 1914 two lines of trenches stretched some 700 kilometres (about 440 miles) across France and Belgium. Neither side could break the other. They would stay there for more than four years.
Keep scrolling — the timeline moves sideways.
On 28 June Archduke Franz Ferdinand of Austria-Hungary is assassinated. Within weeks, alliances turn a regional crisis into a continental war. Germany invades Belgium on 4 August; Britain declares war the same day.
French and British forces halt the German drive on Paris. Both armies race north trying to outflank each other — and when the race ends, they dig in. The Western Front is born.
On Christmas Eve, carols drift across the wire. Soldiers climb out, swap cigarettes and photographs, bury their dead together — and in places, kick a football about. Commanders made sure it was never repeated.
On 22 April German troops release chlorine gas at Ypres. Within a year both sides use gas shells, and soldiers learn to live — and sleep — in gas masks.
Germany attacks the fortress ring of Verdun, aiming to “bleed France white”. The battle grinds on for ten months and costs on the order of 700,000 casualties on both sides. France holds.
On the first day of the Somme the British Army suffers about 57,000 casualties, roughly 19,000 of them killed. The offensive lasts until November, with over a million casualties in all. Tanks appear for the first time in September.
After German unrestricted submarine warfare sinks American ships, the United States declares war. Its Doughboys will take a year to arrive in strength — but they bring fresh millions to a worn-out front.
The Third Battle of Ypres turns a shattered, drained landscape into a swamp under the heaviest rain in years. Men and horses drown in shell holes for gains measured in yards.
With Russia out of the war, Germany throws everything west to win before the Americans arrive. The Allied line bends, deep, but does not break — and the attackers are spent.
The American Expeditionary Forces launch the largest offensive in US military history. 47 days of fighting through forest and ravine cost some 26,000 American lives — and help force the end.
At the eleventh hour of the eleventh day of the eleventh month, the Armistice takes effect. After four years the front goes quiet. Men remember the silence more than any bang.
The Treaty of Versailles is signed on 28 June, five years to the day after Sarajevo. The war to end all wars leaves a world still looking for peace.
A trench was never a simple ditch. It was a zig-zagging, engineered system designed to stop a single shell from clearing a whole line. Pick a part below to see how it worked.
Industry changed warfare faster than generals could change their minds. Hover or tap a card to turn it over.
shells fired in the days before the Somme alone. Artillery caused the majority of battlefield casualties — and its thunder is what drove men into the dugouts and, sometimes, out of their minds.
rounds a minute from a heavy Vickers or Maxim — one crew with the firepower of dozens of riflemen. Open ground became a killing zone, and the trench became the only answer.
estimated gas casualties, around 90,000 of them fatal. Chlorine, phosgene, then mustard gas — and a whole life lived with a gas mask at the hip.
The British send the first tanks into battle on the Somme in September. Slow, hot and unreliable at first, they crushed wire and crossed trenches — and by 1918 they were helping to end the deadlock.
Aircraft began as scouts and ended as fighters, bombers and the eyes of the artillery. The Royal Air Force — the world's first independent air service — was born on 1 April 1918.
Letters were the lifeline of the trench. Soldiers wrote about weather, food, football and homesickness — and tried not to write about anything else. Millions of letters crossed the Channel every week.
The letter on the right is imagined — composed from the many real accounts of Christmas 1914 — and is not a quotation from any one soldier.
Dear Mother,
You will not believe what happened last night. Around dusk the guns went quiet, and then we heard singing from across the wire — the same carol we sang at home. By morning there were men standing in the open on both sides, shaking hands.
We swapped cigarettes. Someone found a football. For a few hours it was only men again.
Your loving son — somewhere in Flanders
When the United States entered the war in April 1917 it had a small army and no experience of this kind of fighting. Within eighteen months, roughly two million American soldiers had crossed the Atlantic to France.
They arrived fresh, determined and in huge numbers just as the exhausted armies of Europe ran out of men. More than 116,000 Americans died in the war — roughly half of them to disease, including the influenza pandemic. They are the “Doughboys”, as American soldiers of the war were nicknamed.
The United States declares war on Germany.
The first American units land in France.
First major American offensive, at Cantigny.
Belleau Wood — Marines hold the line against the German drive on Paris.
The Meuse-Argonne Offensive: the largest operation in American military history, ending on Armistice morning.
Every year at 11:00 on 11 November, the world falls silent for the ones who never came home. The next Armistice Day is in:
