A History of the First World War in 100 Moments: The ‘blackest day’ of the German army - and the assault that finally broke its spirit

John Lichfield describes the unexpectedly spectacular Allied breakthrough that launched a 100-day push to victory

Captured German officers receiving orders from a French officer (Universal Images Group/Getty Images)

On 8 August 1918, trench warfare suddenly became obsolete. British, Canadian, Australian and French troops, backed by 456 tanks and 2,000 guns and howitzers, overwhelmed the Germans on a 14-mile front east of Amiens.

For the first time since the war began, a large German force collapsed under fire. The Allies advanced eight miles, captured 400 guns and took 12,000 prisoners.

Over the next 100 days, the Germans recovered and often fought as stubbornly as ever. But the Allies, strengthened by American troops, had developed new tactics and new weapons. To their own surprise, they pushed the Germans back, very slowly and very bloodily, to the Belgian border.

“August 8th was the blackest day for the German army in the history of this war,” the German commander, Erich von Ludendorff, wrote later.

“Whole bodies of our men surrendered to single troopers, or isolated squadrons.

“Retiring troops, meeting a fresh division going bravely into action, shouted out things like ‘blackleg’ and ‘you’re prolonging the war’, expressions that were to be heard again later.”

The day before, Kaiser Wilhelm, a marginal figure by this time, had warned Ludendorff: “We have reached the limits of our capacity. The war must be ended.”

In March, the German high command had launched a final great offensive to try to win the war – or force favourable peace terms – before American manpower and industrial strength could be fully deployed. After initial success, the offensive had wound down in July, with titanic German losses.

By the summer of 1918, American troops were pouring into Europe in great numbers. British troops were returning from Palestine. The Prime Minister, David Lloyd George, had agreed to release new divisions of British conscripts which he had held back in the spring, fearing that Field Marshal Douglas Haig would feed them uselessly into another meat-grinder like the Somme or Passchendaele.

A flurry of Allied offensives, like a series of boxers’ jabs – the French and Americans in the south; the Canadians, Australians and British in the north – pushed the Germans slowly back over the blood-soaked ground they had captured between March and June.

The Allied generals now had hundreds of improved tanks to spearhead their attacks. They had more accurate and better-organised artillery which could deliver effective, creeping barrages for the first time. They had learnt, finally, how to combine artillery, infantry, tanks and aircraft.

By mid-September, the Germans had retreated behind their great bastion, the Hindenburg Line, three miles in depth. Would a new static war of mud, trenches and barbed-wire prolong the conflict into 1919 or even 1920?

In late September, the British and French and the remnant of the Belgian army attacked near Ypres in the north. The British, Canadians, Australians, Americans and French assaulted the centre of the German line near Saint Quentin. The Americans and the French launched the Meuse-Argonne offensive in the south.

After 10 days of vicious fighting, the British, Australians and Americans broke through near Saint Quentin. The last prepared German positions were overrun by 5 October.

The new weapons and tactics helped. But so did the exhaustion of the German troops. The attack on Saint Quentin was planned by General Sir Henry Rawlinson, the one-time apostle of attrition, the unimaginative butcher of the Somme in 1916. He had been converted to the new, open warfare, allegedly more “economical” with soldiers’ lives.

He wrote at the time: “Had the Boche [Germans] not shown marked signs of deterioration during the past month, I should never have contemplated attacking the Hindenburg Line. Had it been defended by the Germans of two years ago, it would certainly have been impregnable.”

In truth, the 100 days campaign was not economical with lives. The warfare might be more open and more mechanised but the “poor, bloody infantry” still died in droves.

The battles of 1918 – Amiens, Montdidier, Bapaume, Mont Saint-Quentin, Vauxaillon, Epehy – have not been pounded into our collective memory like Verdun, the Somme or Passchendaele. It is easy to assume that they were comparatively painless. New weapons and tactics or not, the casualty figures for the “100 days” of battles which ended the war tell a rather different story.

The French suffered 531,000 casualties (dead, wounded and captured) in those three months, roughly as many as in the eight months of Verdun in 1916. The British (including Empire troops) had 411,000 casualties – almost exactly the same as in the four-and-a-half months of the Somme. The Americans suffered 127,000 casualties, more than double the total number of American casualties in the Vietnam War.

German casualties were devastating: 785,000 killed and wounded and 386,000 prisoners – more than a million men in three months.

Read more: The troops from around the world that served Britain in WW1

One of the “British” casualties was an obscure second lieutenant in the Manchester Regiment who was killed in the crossing of the Sambre-Oise canal on 4 November. His name was Wilfred Owen. His poems, not yet published, would come to define the war. But the sense of catastrophic loss was, overwhelmingly, on the other side. Weeks before they signed the Armistice, Ludendorff and the rest of the German high command knew the war was lost. Despite the continuing horrendous losses, however, and starvation and civil unrest in Germany, they refused to seek terms.

By this time Germany was virtually a military dictatorship and the wishes of civilian politicians counted for little. Nonetheless, the generals insisted that it was for the civilian leadership to put up the white flag, not the army.

Tens of thousands of men died in the final days while Ludendorff played this game. Eventually, the Armistice was signed but a myth was created that the German army had never been defeated in the field. It had been “stabbed in the back” by politicians and left-wing revolutionaries at home. Within two decades, that myth helped to fuel the rise of the Nazis and the start of another war.

Tomorrow: America’s biggest battle

The '100 Moments' already published can be seen at: independent.co.uk/greatwar