Battle of Amiens ( 1918 ) The Battle of Amiens ( also known as the Third Battle of Picardy ( ) ) , which began on 8 August 1918 , was the opening phase of the Allied offensive later known as the Hundred Days Offensive that ultimately led to the end of the First World War . Allied forces advanced over seven miles on the first day , one of the greatest advances of the war , with Henry Rawlinson ' s British Fourth Army playing the decisive role . The battle is also notable for its effects on both sides ' morale and the large number of surrendering German forces . This led Erich Ludendorff to describe the first day of the battle as " the black day of the German Army " . Amiens was one of the first major battles involving armoured warfare and marked the end of trench warfare on the Western Front , fighting becoming mobile once again until the armistice was signed on 11 November 1918 . Prelude . On 21 March 1918 , the German Empire had launched Operation " Michael " , the first in a series of attacks planned to drive the Allies back along the length of the Western Front . With the signing of the Treaty of Brest - Litovsk with revolutionary - controlled Russia , the Germans were able to transfer hundreds of thousands of men to the Western Front , giving them a significant , if temporary , advantage in manpower and material . These offensives were intended to translate this advantage into victory . Operation " Michael " was intended to defeat the right wing of the British Expeditionary Force , but a lack of success before Arras ensured the ultimate failure of the offensive . A final effort was aimed at the town of Amiens , a vital railway junction , but the advance had been halted at Villers - Bretonneux by the Australians supported by other units scraped together on a piecemeal basis on 4 April . Subsequent German offensives — Operation " Georgette " ( 9 April – 11 April ) , Operation " Blücher - Yorck " ( 27 May ) , Operation " Gneisenau " ( 9 June ) and Operation " Marne - Rheims " ( 15 July – 17 July ) — all made advances elsewhere on the Western Front , but failed to achieve a decisive breakthrough . By the end of the Marne - Rheims offensive , the German manpower advantage had been spent and their supplies and troops were exhausted . The Allied generalissimo , General Ferdinand Foch , ordered a counteroffensive which led to the Second Battle of the Marne , after which victory he was promoted to Marshal of France . The Germans , recognising their untenable position , withdrew from the Marne to the north . Foch now tried to move the Allies back onto the offensive . Plan . Foch disclosed his plan on 23 July 1918 , following the German retreat that had begun on 20 July . The plan called for reducing the Saint - Mihiel salient ( which would later see combat in the Battle of Saint - Mihiel ) and liberating the railway lines that ran through Amiens . The commander of the British Expeditionary Force , Field Marshal Sir Douglas Haig , already had plans in place for an attack near Amiens . When the British retreat had ended in April , the headquarters of the British Fourth Army under General Sir Henry Rawlinson had taken over the front astride the Somme . Its left hand corps was the British III Corps under Lieutenant General Richard Butler , while the Australian Corps under John Monash held the right flank and linked up with French armies to the south . On 30 May , all the Australian infantry divisions were united under the corps HQ , for the first time on the Western Front . The Australians had mounted a number of local counter - attacks which both revealed the suitability of the open and firm terrain south of the Somme for a larger offensive and also established and refined the methods which were to be used . Rawlinson had submitted Monash ' s proposals to Haig in July and Haig had forwarded them to Foch . At a meeting on 24 July , Foch agreed to the plan but insisted that the French First Army , which held the front to the south of the British Fourth Army , should participate . Rawlinson opposed this as his and Monash ' s plans depended on the large - scale use of tanks ( now finally available in large numbers ) to achieve surprise , by avoiding a preliminary bombardment . The French First Army lacked tanks and would be forced to bombard the German positions before the infantry advance began , thus removing the element of surprise . Eventually , it was agreed that the French would participate , but not launch their attack until 45 minutes after the Fourth Army . It was also agreed to advance the proposed date of the attack from 10 August to 8 August , to strike the Germans before they had completed their withdrawal from the Marne salient . Rawlinson had already finalised his plans in discussion with his Corps commanders ( Butler , Monash , Sir Arthur Currie of the Canadian Corps and Lieutenant General Charles Kavanagh of the Cavalry Corps ) on 21 July . For the first time , the Australians would attack side by side with the Canadian Corps . Both had a reputation for aggressive and innovative tactics and a strong record of success over the past two years . The tactical methods had been tested by the Australians in a local counter - attack at the Battle of Hamel on 4 July . The German defenders of Hamel were deeply dug in , and their position commanded a very wide field of fire . Similar positions had resisted capture for two months in the Battle of the Somme . The Australians had used surprise rather than weight at Hamel . The artillery had opened fire only at the moment the infantry and tanks advanced , and the Germans were rapidly overrun . A key factor in the final plan was secrecy . There was to be no pre - battle bombardment , only artillery fire immediately prior to the advance of Australian , Canadian , and British forces . The final plan for the Fourth Army involved 1 , 386 field guns and howitzer s and 684 heavy guns , making up 27 medium artillery brigades and thirteen heavy batteries , in addition to the infantry divisions ' artillery . The fire plan for the Fourth Army ' s artillery was devised by Monash ' s senior artillery officer , Major General C . E . D . Budworth . British sound ranging advances in artillery techniques and aerial photographic reconnaissance made it possible to dispense with " ranging shots " to ensure accurate fire . Budworth had produced a timetable which allowed 504 out of 530 German guns to be hit at " zero hour " , while a creeping barrage preceded the infantry . This method was similar to the " Feuerwalze " which the Germans themselves had used in their Spring Offensive , but its effectiveness was increased by the surprise achieved . There were also to be 580 tanks . The Canadian and Australian Corps were each allocated a brigade of four battalions , with 108 Mark V fighting tanks , 36 Mark V " Star " tanks capable of carrying a squad of infantry armed with a Lewis gun and 24 unarmed tanks intended to carry supplies and ammunition forward . A single battalion of Mark V tanks was allocated to III Corps . The Cavalry Corps were allocated two battalions each of 48 Medium Mark A Whippet tanks . The Allies had successfully moved the Canadian Corps of four infantry divisions to Amiens without them being detected by the Germans . This was a noteworthy achievement and reflected well on the increasingly efficient staffwork of the British armies . A detachment from the Corps of two infantry battalions , a wireless unit and a casualty clearing station had been sent to the front near Ypres to bluff the Germans that the entire Corps was moving north to Flanders . The Canadian Corps was not fully in position until 7 August . To maintain secrecy , the Allied commanders pasted the notice " Keep Your Mouth Shut " into orders issued to the men , and referred to the action as a " raid " rather than an " offensive " . Preliminaries . Although the Germans were still on the offensive in late July 1918 , the Allied armies were growing in strength , as more American units arrived in France , and British reinforcements were transferred from the Home Army in Britain and the Sinai and Palestine Campaign . The German commanders realized in early August that their forces might be forced onto the defensive , though Amiens was not considered to be a likely front . The Germans believed the French would probably attack the Saint - Mihiel front east of Rheims , or in Flanders near Mount Kemmel , while they believed the British would attack along either the Lys or near Albert . The Allies had indeed mounted a number of local counter - offensives in these sectors , both to gain local objectives to improve their defensive positions and to distract attention from the Amiens sector . German forces began to withdraw from the Lys and other fronts in response to these theories . The Allies maintained equal artillery and air fire along their various fronts , moving troops only at night , and feigning movements during the day to mask their actual intent . The German front east of Amiens was held by their Second Army under General Georg von der Marwitz , with six divisions in line ( and two facing the French 1st Army ) . There were only two divisions in immediate reserve . There was some concern among the Allies on 6 August when the German 27th Division actually attacked north of the Somme on part of the front on which the Allies planned to attack two days later . The German division ( a specially selected and trained " Stosstruppen " formation ) penetrated roughly into the one - and - a - half mile front . This attack was made in retaliation for a trench raid by the 5th Australian Division north of the Somme on the night of 31 July , which had gained many prisoners , before the Australian Corps was concentrated south of the river . The German division moved somewhat back to its original position on the morning of 7 August , but the movement still required changes to the Allied plan . Battle . The battle began in dense fog at 4 : 20 am on 8 August 1918 . Under Rawlinson ' s Fourth Army , the British III Corps attacked north of the Somme , the Australian Corps to the south of the river in the centre of Fourth Army ' s front , and the Canadian Corps to the south of the Australians . The French 1st Army under General Debeney opened its preliminary bombardment at the same time , and began its advance 45 minutes later , supported by a battalion of 72 Whippet tanks . Although German forces were on the alert , this was largely in anticipation of possible retaliation for their incursion on the sixth and not because they had learned of the preplanned Allied attack . Although the two forces were within of one another , gas bombardment was very low , as the bulk of the Allied presence was unknown to the Germans . The attack was so unexpected that German forces only began to return fire after five minutes , and even then at the positions where the Allied forces had assembled at the start of the battle and had long since left . In the first phase , seven divisions attacked : the British 18th ( Eastern ) and 58th ( 2 / 1st London ) , the Australian 2nd and 3rd , and the Canadian 1st , 2nd and 3rd Divisions . Parts of the American 33rd Division supported the British attackers north of the Somme . The attackers captured the first German position , advancing about by about 7 : 30 am In the centre , supporting units following the leading divisions attacked the second objective a further distant . Australian units reached their first objectives by 7 : 10 am , and by 8 : 20 am , the Australian 4th and 5th Divisions and the Canadian 4th Division passed through the initial breach in the German lines . The third phase of the attack was assigned to infantry - carrying Mark V * tanks . However , the infantry was able to carry out this final step unaided . The Allies penetrated well to the rear of the German defences and cavalry now continued the advance , one brigade in the Australian sector and two cavalry divisions in the Canadian sector . RAF and armoured car fire kept the retreating Germans from rallying . The Canadian and Australian forces in the centre advanced quickly , pushing the line forward from its starting point by 11 : 00 am . The speed of their advance was such that a party of German officers and some divisional staff were captured while eating breakfast . A gap long was punched in the German line south of the Somme by the end of the day . There was less success north of the river , where the British III Corps had only a single tank battalion in support , the terrain was rougher and the German incursion of 6 August had disrupted some of the preparations . Although the attackers gained their first objectives , they were held up short of the Chipilly Spur , a steep wooded ridge . The British Fourth Army took 13 , 000 prisoners while the French captured a further 3 , 000 . Total German losses were estimated to be 30 , 000 on 8 August . The Fourth Army ' s casualties , British , Australian and Canadian infantry , were approximately 8 , 800 , exclusive of tank and air losses and those of their French allies . German Army Chief of Staff Paul von Hindenburg noted the Allies ' use of surprise and that Allied destruction of German lines of communication had hampered potential German counter - attacks by isolating command positions . The German General Erich Ludendorff described the first day of Amiens as ( " the black day of the German Army " ) , not because of the ground lost to the advancing Allies , but because the morale of the German troops had sunk to the point where large numbers of troops began to capitulate . He recounted instances of retreating troops shouting " You ' re prolonging the war ! " at officers who tried to rally them , and " Blackleg ! " at reserves moving up . Five German divisions had effectively been engulfed . Allied forces pushed , on average , into enemy territory by the end of the day . The Canadians gained , Australians , British , and the French . Later fighting . The advance continued on 9 August , though not with the same spectacular results of the first day . The battle was widened on the north and the south of the initial attack ( with the southern part of the battle ( involving French forces ) called Battle of Montdidier ( ) ) . The infantry had outrun the supporting artillery and the initial force of more than 500 tanks that played a large role in the Allied success was reduced to six tanks fit for battle within four days . The Germans on Chipilly Spur commanded a wide field of fire to the south of the Somme , and their flanking fire held up the left units of the Australian Corps until late on 9 August , when a small Australian party slipped across the river and captured the village of Chipilly itself , together with a renewed attack by III Corps . On the Canadian front , congested roads and communication problems prevented the British 32nd Division being pushed forward rapidly enough to maintain the momentum of the advance . On 10 August , there were signs that the Germans were pulling out of the salient from Operation " Michael " . According to official reports , the Allies had captured nearly 50 , 000 prisoners and 500 guns by 27 August . Even with the lessened armour the British drove into German positions by 13 August . Field Marshal Haig refused the request of Marshal Foch to continue the offensive , preferring instead to launch a fresh offensive by Byng ' s Third Army between the Ancre and Scarpe . Aftermath . The Battle of Amiens was a major turning point in the tempo of the war . The Germans had started the offensive with the Schlieffen Plan before the Race to the Sea slowed movement on the Western Front and the war devolved into trench warfare . The German Spring Offensive earlier that year had once again given Germany the offensive edge on the Western Front . Armoured support helped the Allies tear a hole through trench lines , weakening once impregnable trench positions . The British Third Army with no armoured support had almost no effect on the line while the Fourth , with fewer than a thousand tanks , broke deep into German territory . Australian commander John Monash was knight ed by King George V in the days following the battle . British war correspondent Philip Gibbs noted Amiens ' effect on the war ' s tempo , saying on 27 August that , " the enemy . . . is on the defensive " and , " the initiative of attack is so completely in our hands that we are able to strike him at many different places . " Gibbs also credits Amiens with a shift in troop morale , saying , " the change has been greater in the minds of men than in the taking of territory . On our side the army seems to be buoyed up with the enormous hope of getting on with this business quickly " and that , " there is a change also in the enemy ' s mind . They no longer have even a dim hope of victory on this western front . All they hope for now is to defend themselves long enough to gain peace by negotiation . "