Second Battle of the Somme ( 1918 ) During the First World War , the Second Battle of the Somme of 1918 was fought on the Western Front from the end of the summer , in the basin of the Somme River . It was part of a series of successful counter - offensives in response to the German Spring Offensive , after a pause for redeployment and supply . The most significant feature of the 1918 Somme battles was that with the first Battle of the Somme of 1918 having halted what had begun as an overwhelming German offensive , the second formed the central part of the Allies ' advance to the Armistice of 11 November . Battle . On 15 August 1918 , Field Marshal Douglas Haig refused demands from Marshal Ferdinand Foch to continue the Amiens offensive , as that attack was faltering as the troops outran their supplies and artillery , and German reserves were being moved to the sector . Instead , Haig began to plan for an offensive at Albert , which opened on 21 August . The main attack was launched by the British Third Army , with the United States II Corps attached . The second battle began on 21 August with the opening of the Second Battle of Bapaume to the north of the river itself . That developed into an advance which pushed the German Second Army back over a 55 kilometre front , from south of Douai to La Fère , south of Saint - Quentin , Aisne . Albert was captured in 22 August . On 26 August , the British First Army widened the attack by another twelve kilometres , sometimes called the Second Battle of Arras . Bapaume fell on 29 August . The Australian Corps crossed the Somme River on the night of 31 August , and broke the German lines at the Battle of Mont St . Quentin and the Battle of Péronne . The British Fourth Army ' s commander , General Henry Rawlinson , described the Australian advances of 31 August – 4 September as the greatest military achievement of the war . On the morning of 2 September , after a heavy battle , the Canadian Corps seized control of the Drocourt - Quéant line ( representing the west edge of the Hindenburg Line ) . The battle was fought by the Canadian 1st Division , 4th Division , and by the British 52nd Division . Heavy German casualties were inflicted , and the Canadians also captured more than 6 , 000 unwounded prisoners . Canada ' s losses amounted to 5 , 600 . By noon that day the German commander , Erich Ludendorff , had decided to withdraw behind the Canal du Nord . By 2 September , the Germans had been forced back to the Hindenburg Line , from which they had launched their offensive in the spring . On their way to the Hindenburg Line , in a fierce battle , the Canadian troops , led by General Sir Arthur Currie , overcame the earthworks of the incomplete Canal du Nord during the Battle of Canal du Nord . In late September / early October , one of the epic battles of the whole war was the breach of the Hindenburg Line ( the Battle of St . Quentin Canal ) by British , Australian and American troops ( under the command of Australian General John Monash ) . Soon after , the Canadians breached the Hindenburg Line at the Battle of Cambrai . A key part of the German supply line ran parallel with the front . This second 1918 battle around the Somme was part of a strategy designed to push parts of the German line back behind this main supply line so cutting it and making the efficient maintenance of the German forces on the front , impossible . The campaign began with battle of Bapaume and , starting shortly after , the Battle of Saint - Mihiel , outside the Somme area , with the aim of reducing salients before using the fluidity of the broken line to press on to the strategic railway . It was hoped that this fluidity would be present as , owing to the German advance in the spring , the German forces were well in advance of their hitherto impregnable , very well prepared defences on the Hindenburg Line . This policy worked but it took some very determined work at the St . Quentin Canal , among the prepared defences , to achieve success .