Hundred Days Offensive

The Hundred Days Offensive is the name of the series of attacks in which, from 8 August to 11 November 1918, the Allied armies on the Western Front, under the joint direction of Marshal Ferdinand Foch, defeated the German army. It began with the blow struck by the British, Canadians, Australians and French at Amiens, which General Erich Ludendorff called “the black day of the German army”. After that the Allies gave the Germans no respite. They struck in turn at ever new points, retook the ground the Germans had won in the spring, at the end of September attacked simultaneously along the whole front from Flanders to the Meuse, and broke the Hindenburg Line, the strongest German position in the west. In October and early November they pushed the Germans back through northern France and Belgium towards the Meuse. The defeats at the front, together with the capitulation of Germany’s allies, led the German Supreme Army Command to demand an armistice, which was signed on 11 November in the forest of Compiègne.

Name and dates

The name “Hundred Days” comes from British writing. It was popularised among others by a book published in 1919 by General Archibald Montgomery, chief of staff of the British Fourth Army, on “the Battle of the Hundred Days, August 8th to November 11th, 1918”. In fact 95 days passed between the first day of the attack at Amiens and the armistice. It was not a single planned operation but a sequence of battles that were only grouped into one whole after the war. French historiography speaks rather of Foch’s counter-offensives, and in Canada the name “Canada’s Hundred Days” took hold. We adopt the commonly used dates of 8 August – 11 November 1918. The counter-offensive on the Marne, which from 18 July took the initiative from the Germans, we describe separately as the Second Battle of the Marne.

We name and date the individual battles that make up the offensive chiefly according to the British Battles Nomenclature Committee, since most of them were fought by British armies: the Battle of Amiens, the Second Battle of the Somme (with the Battles of Albert and of Bapaume), the Battle of the Scarpe, the Battle of the Drocourt–Quéant Line, the Battles of the Hindenburg Line, the Fifth Battle of Ypres, the Battle of Courtrai, the Battle of the Selle, the Battle of Valenciennes and the Battle of the Sambre. The French attacks (the Battles of Montdidier and Noyon) and the American ones (at Saint-Mihiel and between the Meuse and the Argonne) have names and dates of their own, often different from those in the British lists. We give figures chiefly from the British official history (James Edmonds, Military Operations France and Belgium 1918, volumes IV and V) and the final despatch of Field Marshal Douglas Haig.

Background

In the spring of 1918 Ludendorff tried to decide the war before masses of American troops reached France. Operation Michael in March, the Battle of the Lys in April and further blows on the Aisne and the Marne brought the Germans their greatest gains since 1914, but no decision. The crisis forced the Allies to unify their command: at Doullens they entrusted Foch with coordinating the operations of their armies, and in April appointed him commander-in-chief. The offensives cost the Germans hundreds of thousands of men, among them their best storm divisions, which they had nothing to replace with, and their gains took the form of long salients that were hard to defend. The Allies, by contrast, received hundreds of thousands of fresh American soldiers every month and in the summer regained numerical superiority.

On 18 July Foch threw into a counter-offensive the French Tenth Army of General Charles Mangin against the western flank of the German salient on the Marne, and by early August the Germans had to abandon it. On 24 July, while that battle was still going on, Foch gathered the three commanders-in-chief at his headquarters in the Château de Bombon near Melun: Haig, General Philippe Pétain and General John Pershing. He laid before them a plan for a series of limited attacks to free three railways important for further operations: Paris–Avricourt on the Marne, Paris–Amiens, threatened from the Montdidier salient, and Paris–Avricourt near Saint-Mihiel. The task at Amiens went to the British Fourth Army of General Henry Rawlinson and the French First Army of General Marie-Eugène Debeney. The model was to be the attack by the Australians of General John Monash at Hamel on 4 July: surprise instead of a bombardment lasting days, and close cooperation of infantry, tanks, artillery and aircraft. On 6 August Foch was made a Marshal of France.

Amiens and the retreat to the Somme (8 August – 3 September)

At dawn on 8 August, in fog and without any preliminary artillery bombardment, Rawlinson’s Fourth Army, with the Canadian Corps of General Arthur Currie and Monash’s Australian Corps as its main striking force and more than four hundred tanks, attacked east of Amiens. The German Second Army of General Georg von der Marwitz was taken completely by surprise. By evening the Allies had advanced 12–13 kilometres and taken about 15,000 prisoners. On the right wing the French First Army attacked, joined from 10 August by the Third Army of General Georges Humbert, which retook Montdidier. In the following days the attack bogged down in old trenches from 1915–1916, and on 11 August Haig halted it. Ludendorff, who received reports of units surrendering to single horsemen and of soldiers shouting “strike-breakers” at those going up to the front, concluded that a new offensive was no longer conceivable. On 14 August the crown council at Spa admitted that the war could not be won militarily, but decided to seek peace only at a “suitable moment”.

Haig drew the lesson from Amiens that instead of breaking through an ever stronger defence, the blow should be struck at a new point. Foch therefore extended the attack on the flanks. On 17 August the French Tenth and Third Armies attacked between the Oise and the Aisne, and on 20 August Mangin broke through the front near Soissons. Ludendorff called that day “another black day”, and on 29 August the French retook Noyon. In Flanders the British took Outtersteene Ridge on 18 August, after which the Germans began to abandon the Lys salient won in April, including Bailleul and Mount Kemmel. On 21 August the British Third Army of General Julian Byng went into action north of the Somme. In the Second Battle of the Somme the British, Australians and New Zealanders retook Albert, Bapaume and Péronne in less than two weeks, and on 31 August and 1 September the Australians took Mont Saint-Quentin. From 26 August the First Army of General Henry Horne was also attacking east of Arras. The Canadians retook Monchy-le-Preux, and on 2 September they broke the Drocourt–Quéant Line, a strong position covering the Hindenburg Line from the north. That same day the German Supreme Army Command decided to withdraw the armies behind the Canal du Nord and onto the Hindenburg Line, from which they had set out on the spring offensive.

The approaches to the Hindenburg Line and Saint-Mihiel (September)

Foch had long wanted, as the British official history puts it, to employ “all the Allied forces in convergent action”. In a note of 30 August and a directive of 3 September he set out the directions: the British armies, supported by the French left wing, were to attack towards Cambrai and Saint-Quentin, the French centre was to drive the Germans beyond the Aisne, and the Americans with the French right wing were to strike astride the Meuse in the direction of Mézières. Through Mézières ran one of the two main railway lines supplying the German armies on the Western Front. On 9 September Foch added to the plan an attack in Flanders, where the Flanders Army Group was formed under the command of the King of the Belgians, Albert I, with the Belgian army, the British Second Army of General Herbert Plumer and French divisions.

Before that, on 12 September, Pershing’s American First Army, with the French II Colonial Corps, attacked the German salient at Saint-Mihiel, which since 1914 had cut into the French lines south-east of Verdun. The attack surprised the Germans just as they were beginning to evacuate the salient, and eliminated it in two days. The Americans took about 15,000–16,000 prisoners and about 450 guns. It was the first great operation of an independent American army. The same day the British took Havrincourt, an advanced bastion of the Hindenburg Line, and on 18 September at Épehy the Fourth Army, with the Australians in the centre, cleared its outpost zone. To the south of them the French First Army closed up to Saint-Quentin.

The great offensive along the whole front (26 September – 12 October)

At the end of September Foch attacked along the whole front at once, on four successive days. On 26 September the American First Army and the French Fourth Army of General Henri Gouraud advanced between the Meuse and the Argonne and in Champagne. On 27 September the Canadians and the British Third Army crossed the dry stretch of the Canal du Nord and took Bourlon Wood in front of Cambrai. On 28 September the Flanders Army Group in a single day retook the heights around Ypres, which in 1917 had been fought over for more than three months. On 29 September the British Fourth Army, with the American II Corps and the Australians, attacked the main position of the Hindenburg Line on the St Quentin Canal. The 46th Division crossed the canal at Bellenglise, and by 5 October the British and Australians had also taken the Beaurevoir Line, the last position of that system. On 1 October the French entered ruined Saint-Quentin.

The attacks coincided with the collapse of Germany’s allies. On 29 September Bulgaria, routed in the Vardar offensive, signed an armistice at Salonika. On the evening of 28 September Ludendorff and Field Marshal Paul von Hindenburg decided to demand an armistice, and on 29 September at Spa they demanded from the Kaiser and the government an immediate request for one. On the night of 3–4 October the new chancellor, Prince Max von Baden, sent a note to President Woodrow Wilson. The fighting nevertheless went on. On 8 October the British Third and Fourth Armies with the Americans passed through the unfinished German positions near Cambrai into open country, and on 9 October the Canadians and British entered the burning city. By 12 October the Germans had fallen back to the river Selle, to the new Hermann position, which was still being built. Between the Meuse and the Argonne, by contrast, the Americans advanced slowly and at a high price: after a brilliant first day they got stuck in traffic jams and under fire from both flanks, and throughout October they bled in frontal attacks on successive belts of fortifications.

The pursuit towards the Meuse and the Sambre (13 October – 11 November)

On 13 October the French entered Laon and La Fère, and on 14 October the Flanders Army Group attacked again. In the Battle of Courtrai it broke the last German position in West Flanders, and the German Supreme Army Command decided that there was no longer any point in defending the coast or Lille. On 17 October the Germans gave up Ostend, Douai and Lille without a fight, and by 20 October the whole Belgian coast was free. That same day, 17 October, the British Fourth Army with the Americans forced the Selle near Le Cateau, from where the British Expeditionary Force had retreated in August 1914. By 25 October three British armies had pushed the Germans back as far as the Sambre–Oise Canal, the Forest of Mormal and Valenciennes. Meanwhile, in mid-October, the Americans broke through the main German position between the Meuse and the Argonne, the so-called Kriemhilde position. In Berlin Ludendorff wanted to fight on again, but after his order rejecting Wilson’s note the Kaiser accepted his resignation on 26 October. His place was taken by General Wilhelm Groener.

In early November the German defence fell apart. On 1 November the Americans resumed the attack between the Meuse and the Argonne and this time broke through the front. That same day the Canadians took Mont Houy, and on 2 November Valenciennes. On 4 November three British armies, with the French First Army on their right wing, crossed the Sambre–Oise Canal, passed through the Forest of Mormal and took the fortress of Le Quesnoy. It was the last great battle of the British army in this war. On the night of 4–5 November the German Second Army began to fall back to the Antwerp–Meuse position, and on 6 November the order to retreat was extended to all the armies. Revolution had already broken out in Germany, begun on 3 November by the sailors’ mutiny at Kiel. On 6–7 November the Americans reached the heights above Sedan, and on 8 November the German delegation with State Secretary Matthias Erzberger stood before Foch in the forest of Compiègne. In the last days the British entered Maubeuge, the Belgians Ghent, the French Mézières, and on the morning of 11 November the Canadians Mons, where in August 1914 the British had fought their first battle. At dawn on 11 November the Germans signed the armistice in Foch’s railway carriage, and at 11 o’clock the guns fell silent on the Western Front.

Casualties

The Hundred Days Offensive was one of the bloodiest periods of the war. According to figures cited by the American historian Spencer Tucker, from 18 July to 11 November the Allies lost about 1.07 million killed, wounded and missing on the Western Front: the French about 531,000, the British armies about 412,000 and the Americans about 127,000. According to War Office figures quoted by Edmonds, the British army lost a total of about 358,000 men in August, September and October 1918, about 121,000 of them in October alone. The Canadian Corps lost more than 45,000 men from 8 August to the armistice, and the American First Army about 117,000 killed and wounded in the offensive between the Meuse and the Argonne alone.

According to the same compilation the Germans lost more than 1.1 million men, including about 386,000 prisoners. Haig wrote in his final despatch that from 8 August to 11 November the British forces took 187,000 prisoners and 2,850 guns (later compilations give 188,700 prisoners and 2,840 guns), and that in this time 59 fighting British divisions defeated 99 German divisions. According to later calculations the French took about 139,000 prisoners and 1,880 guns, the Americans more than 44,000 prisoners and nearly 1,500 guns, and the Belgians about 14,500 prisoners and more than 400 guns. The Canadians alone took about 32,000 prisoners. The German divisions were melting away: in October Crown Prince Rupprecht of Bavaria wrote that a division seldom had more than three thousand infantrymen and that the soldiers surrendered in masses at every attack. On top of the battle losses came the influenza epidemic, which decimated both sides in the autumn.

Significance

The Hundred Days Offensive decided the outcome of the war on the Western Front. In three months the German army lost all the ground won in the spring, the Hindenburg Line, behind which as late as September it had hoped to spend the winter, and most of occupied France and western Belgium. It had no reserves or prepared positions left, and its soldiers increasingly avoided fighting. The defeats at the front, together with Bulgaria’s armistice, convinced Hindenburg and Ludendorff that an armistice must be requested at once. That is precisely why historians reject the later legend of the “stab in the back”: it was the Supreme Army Command, not the politicians, that asked for an armistice, when the army was in retreat. As late as the summer the Allies had assumed that the war would last until 1919.

The victory was the work of many armies. Foch set the direction and pace of the attacks, not allowing the Germans to shift reserves from one threatened sector to another. Haig stressed in his despatch that the British armies, with the Canadian and Australian corps as their shock troops, attacked the strongest and most vital sectors of the German front and took the most prisoners. The French armies, exhausted by four years of war, kept up the pressure along the whole length of the front, and the Americans, though they paid a high price for their lack of experience, tied down dozens of German divisions on the Meuse, where the Germans could least afford to lose ground. The Allies also won because they had learned to fight differently: surprise, fire without registering the guns, masses of tanks, aircraft and efficient logistics made it possible to break the front within a few hours, and instead of forcing one sector to the bitter end they struck in turn at ever new points. The offensive also had its limits. The Allies did not manage to encircle any large German army, and in October and November the pursuit was slowed by destroyed roads, bridges and railways. When the armistice came into force the German armies still stood on French and Belgian soil, but they were no longer capable of fighting on.