The withdrawal of Russia from the war in 1917 released substantial numbers of German troops for use elsewhere. Aware that submarine warfare had failed to defeat Britain and that large numbers of American troops would soon be committed to the war, the Germans prepared for their final offensive. Field Marshal Haig's British divisions were all under-strength in infantry. The government was unwilling to send more troops to the Western Front so Haig was forced to reduce the number of infantry battalions in his divisions.
In mid-February 1918, 81 German divisions faced Haig's 59, and for the first time in three years the British had to prepare to face a major attack. Haig could not afford to give ground near to the Channel coast so the northern sector of his front was most heavily defended while further south his forces were more thinly spread. Whereas General Plumer's Second Army around Ypres had to hold 37 kilometres (23 miles) of line with 14 divisions, south of Cambrai General Gough's Fifth Army only had 14 divisions with which to hold 67 kilometres (42 miles) of line.
On 21 March 1918 the Germans launched Operation MICHAEL. Around 10,000 guns fired over a million shells in five hours against Lieutenant General Byng's Third and General Gough's Fifth Armies before 47 German divisions attacked. Using infiltration tactics the German storm troopers by-passed pockets of resistance and broke through the British trench system, leaving the following waves of troops to 'mop up' any resistance. Lacking reserves, Gough's line soon gave way and by the evening of 23 March the Germans had advanced 19 kilometres (12 miles).
'At 10am the barrage appeared to lift and the sentry shouted down the dugout that the enemy were in on our flanks and behind us. I ran up the dugout steps and already found the trench full of Germans. They were behind us and coming across our flanks...with the signallers and servants, Sergeant Major and the wounded we surrendered. The Bosche were not at all rough and took us over without any roughness.'
Diary entry for the night of 20-21 March 1918 by Captain Ernest Ambler, 1st Battalion, The Prince of Wales's Own (West Yorkshire Regiment)
On 26 March, in exchange for reinforcements, Haig agreed to the appointment of France's Marshal Foch as supreme commander on the Western Front. Although the Germans had advanced as much as 64 kilometres (40 miles), by 5 April their advance began to run out of steam and they were held east of Amiens. Total British losses were 178,000 men. The French who became engaged as the battle developed lost 77,000 and the Germans 240,000.
'Despite his hordes we have held the Bosche all night inflicting huge losses. God only knows whether we shall continue to do so for men are no object to the Huns while our line is thinning hourly.
Up to midnight we still hold, having smashed every Bosche attempt. His losses at this point are extraordinary. Resumption of Hun massed attacks causes us to withdraw through Mézières. He makes great efforts to thrust us back. But he is unsuccessful. Twice the Battalion attack and recapture Mézières but cannot hold it. The Huns are paying very dearly for their gain.'
Diary entry for the night of 27-28 March 1918 by Regimental Quartermaster Sergeant James Littler, 12th Battalion, The King's Royal Rifle Corps
On 9 April the Germans tried again with a smaller offensive south of Ypres, which captured the Messines ridge and much of the Passchendaele salient. Once again the German attack lost momentum. Although they tested the French with a series of offensives further south between 27 May and 17 July, the Germans had shot their bolt. German morale began to crumble and on 18 July the French launched a counter-attack on the Marne, forcing the Germans back. Germany's attempt to break through had exhausted its army and the initiative passed back to the Allies.
Foch began plans for an Allied counter-attack. This was to begin with a series of attacks designed to eliminate the salients created by the German offensive in preparation for a final campaign in 1919. Major General John Pershing's American Expeditionary Force was now present in France and ready for action. The British Army had also been reinforced by large numbers of troops from the Middle East and Italy. The reinforcements that had previously been held back in Britain were also released.
The location chosen for the first Allied counter-stroke was the salient at Amiens on the Somme. The German defences here were relatively weak, having been subjected to continual raiding by the Australians. The landscape was also ideal for the mass deployment of tanks.
On 8 August 1918 General Rawlinson's Fourth Army, spearheaded by the Australian and the Canadian Corps, launched the attack at Amiens. Rawlinson used over 2,000 guns, 450 tanks and 1,900 aeroplanes to support the attack by 13 divisions. Through careful preparations, the Allies achieved complete surprise.
Their tanks broke through the German lines and sowed panic in the rear. The battle illustrated that the British had perfected how to combine infantry, artillery, tanks and aircraft in a co-coordinated attack.
This time it was the German front that broke. A 24 kilometres (15 miles) long gap had been punched in the German line south of the Somme by the end of the advance. The Fourth Army took 13,000 prisoners and over 300 guns. Total German losses were estimated to be 30,000 on 8 August while the Allies suffered about 6,500 killed, wounded and missing. It was the first time that such large-scale capitulations occurred. The German Commander-in-Chief, General Ludendorff called it 'the black day of the German Army' due to the collapse in morale.
Both Ludendorff and Kaiser Wilhelm II now concluded in private that Germany could no longer win the war. The Allied push continued during the next few days but gradually slowed down as the tanks and infantry outran the supporting artillery. Many Allied units were also running short of supplies. On 10 August the Germans began to pull out of the Amiens salient.
Amiens began the period known as the 'Hundred Days', a series of offensives along the line, which drove the Germans back. Much use was made of the Australian and the Canadian Corps in these attacks. On 21 August the British Third Army attacked at Albert and pushed the German Second Army back over a 55 kilometre (34 mile) front. On 26 August, the British First Army widened the attack by another 12 kilometres (seven miles). Bapaume fell on 29 August and the Germans were forced back to the line of the Somme.
As supplies and reinforcements were brought forward, the British Fourth Army also resumed its offensive, and the Australian Corps crossed the River Somme on 31 August, breaking the German lines at St Quentin and Péronne. General Rawlinson described the Australian advance as the greatest military achievement of the war. Between 12 and 18 September 1918 the Allies then reduced the remaining German salients at Havrincourt, St Mihiel, Epehy and Canal du Nord.
Having cleared the salients, Marshal Foch now decided to launch a three-pronged attack against the weakened German lines. In the north, King Albert of Belgium, with a force of British, French and Belgian troops, would attack through Flanders. In the south the French and Americans would attack on the front between Reims and Verdun.
Finally, in the centre of the line, Haig would command three British armies and one French in an attack between Cambrai and St. Quentin. The southern attack made good progress but was then slowed up by supply problems. Nevertheless, by November 1918 the French and Americans had reached Sedan and had cut the Sedan-Metz railway line, one of the main supply lines to the whole German front.
The northern attack began on 28 September 1918 and was also a dramatic success. The British and Belgian armies advanced across the Ypres battlefield and recaptured all the ground lost the previous April. In three days the Allies advanced 16 kilometres (10 miles), reaching the Menin-Roulers road. Bad weather and inadequate planning then delayed the continuation of the offensive, but on 17 October Lille, Ostend and Douai were liberated. The Belgians reached Zeebrugge and Bruges two days later. By the end of the month the Allies were at the Schelde and by the time of the Armistice they had advanced over 80 kilometres (50 miles).
In the central sector, 40 British and Empire divisions supported by the American II Corps faced 57 German divisions protected by the Hindenburg Line, a series of formidable defensive fortifications stretching from Cerny on the River Aisne to Arras. The line had resisted several Allied attacks the previous year and took advantage of a series of wide canals that ran though deep cuttings. The offensive began on 27 September with an attack on the Canal du Nord by the First and Third British Armies that succeeded in overrunning two lines of the defences near Cambrai.
On 30 September the Allies attacked on the St Quentin Canal. Australian and American troops assaulted a strongly defended sector at Bellicourt with tanks, artillery and aircraft once again being used in a co-ordinated attack. Two days later, a British division made an amphibious crossing of the canal to the south. During the following days the Allied attacks met with more success and all the lines were fully breached.
'The great thing now is to get ahead. We had got on to a lovely main road, ahead we can see a railway cutting with a lovely stone bridge crossing it. When we get within a quarter of a mile or so up goes the bridge in the air, with the result that we have to carry the cycles down a very step embankment, follow the railway lines which have been blown up every hundred yards or so, until we can find a place where we can climb up the embankment... We can now see that the Germans must be in full retreat. Trees are cut down, and have fallen across the road, bridges are blown up, all telegraph lines sawn down, canals dammed and roads mined'
Typescript memoir by Second Lieutenant Edwin Blomfield, MC, The New Zealand Cyclist Battalion, 1918
The German army's reserves were severely depleted by four years of war. Likewise, the German economy was suffering from the Allied naval blockade and the home population was on the verge of starvation. The Allied victories during the 'Hundred Days', especially the breaking of the Hindenburg Line, were the final straw for many and German troops began surrendering in larger numbers. Nevertheless, parts of their retreating army continued to fight ferociously and Allied casualties were still very heavy. The British suffered 350,000 casualties between August 1918 and the end of the war in November.
After the breaking of the Hindenburg Line the Germans retreated to a new line running south from Cambrai. On 8 October 1918 the British Third and Fourth Armies and the French First Army attacked along a 27 kilometre (17 mile) front extending south from Cambrai, which was captured the following day. The Allies advanced seven kilometres (four miles) before the Germans took up a new position on the Selle. After a brief pause another successful set-piece attack was launched on 17 October.
'Brigadier comes up at about 5pm to the C.O. [Commanding Officer], Signalling Officer & RSM [Regimental Sergeant Major] both badly hit. Shardley tells me we are to attack the village at 5.30pm as the Heavies are blowing it to bits. A shell at H.Q. causes 10 casualties including the C.O. Move off down road into the village taking second turning on left [with Platoons] in the following order No 11, No 9, No 10, No 12. At turning into town [Le Cateau] we meet a terrible barrage of very heavy shells. A terrible wish to turn back. Awful noise. A big shell lands in the middle of No 11 [Platoon, C Company] a bare 20 yards in front of me. Men and fragments hurled to right and left. One man hurries back with his left knee blown off. I rush my platoon through into the town before the next one comes... Met by a street full of mustard gas.'
Diary entry for 10 October 1918 by Second Lieutenant Alan McPeake, 5th Battalion, The Connaught Rangers
The Germans retreated to another river line, this time on the Sambre. A preliminary attack on 1-2 November saw the Canadians capture Valenciennes, and then on 4 November Haig launched an attack on a 50 kilometre (30 mile) front along the Sambre. This was the final British offensive of the war. When the Armistice came into effect on 11 November 1918, the British were back at Mons where the BEF had first been engaged in 1914. For the first time in its history the British Army had fought and defeated the main body of the main enemy in a European war. Peace came at a huge cost. The mobile warfare since March had cost each side over a million men. 1918 was by far the most costly year of warfare on the Western Front.
'Entering a village as we followed behind the Brigade, our Drums struck up the "Marseilles". The populace became wildly excited, not having heard their National Anthem for a long time. An old man wearing an old fashioned night cap opened a window and leant so far forward, cheering and waving his arms that one feared he might topple out.'
Note by Lance Corporal Frederick Walter, 9th Battalion, The London Regiment, on an armistice order issued by the 169th Infantry Brigade, 11 November 1918