End of the Second Battle of the Somme

At dawn on 3 September 1918 British patrols on the front from the Sensée to the area of the Somme found that there were no longer any Germans in front of them. After the breaking of the Drocourt–Quéant line by the Canadians and the capture of Péronne by the Australians, the German Supreme Army Command ordered a retreat, and on the night of 2/3 September the Seventeenth Army withdrew behind the Sensée and the Canal du Nord. On this day, according to the classification of the British Battles Nomenclature Committee, no fewer than three battles came to an end: the Second Battle of the Somme, which had lasted since 21 August, the Second Battle of Bapaume, which had lasted since 31 August, and the Second Battles of Arras, which had begun on 26 August on the Scarpe and ended with the assault on the Drocourt–Quéant line. The British chronology of the war records all three endings under the same date.

The Germans withdrew gradually, starting from the northern flank. The night was very dark and the British noticed nothing. In the morning airmen confirmed the retreat, and at 10.08 a.m. General Julian Byng, commander of the Third Army, ordered his corps to pursue the enemy with strong advanced guards of all arms. The British 4th Division occupied Étaing on the Sensée, the Canadians reached the western bank of the Canal du Nord, and the 63rd (Royal Naval) Division found Quéant and Pronville abandoned and occupied Inchy. VI Corps advanced almost 10 kilometres, and its cavalry and light tanks came to a halt above the valley beyond which, less than two kilometres away, ran the Hindenburg Line. At the canal the pursuit ended: the bridges had been blown, and German machine guns and artillery were firing from the far bank. In the sector of the Fourth Army of General Henry Rawlinson, the Germans were still holding on along the Somme south of Péronne, and for the Australians it was a day of rest and of preparations for the crossing. The German Second Army began to fall back only the following night.

That same day the headquarters of Field Marshal Douglas Haig issued an order that closed the second stage of the offensive. It stated that the successful operations of the British armies since 8 August had forced the Germans to retreat along almost the whole British front. The armies were now to press the enemy with advanced guards, but for the time being not to undertake large, deliberate attacks; they were to rest, conserve their strength and repair the roads before the offensive was resumed in concert with the Allies. As many divisions as possible were to go into reserve.

The balance sheet was impressive. According to the British official history, from 21 August to 3 September the Fourth Army took 12,414 prisoners, and the Third and First Armies together 33,827. Including the prisoners from Amiens, the British armies had taken almost 65,000 Germans since 8 August. The Third Army advanced on average about 24 kilometres, the First Army about 19, and the Fourth Army 11–22. The cost, however, was high: over the same period the Fourth Army lost about 33,700 men, and the Third Army together with the Canadian Corps about 55,700. According to Edmonds, the Germans threw at least 36 additional divisions against the Third and Fourth Armies, and even so, each time the British won a clear success, they fell back before it could be exploited.

The ground the Germans had won in March in Operation Michael was now mostly lost, and by 9 September their armies were to be back in the positions from which they had launched the spring offensive. In front of the British stood the Canal du Nord and the Hindenburg Line, fortified for a year and a half. The Bavarian official history wrote of the August fighting that the German divisions “simply melted away”, and that, despite requests and entreaties, there were no replacements.