On 29 September, the central attack on the Hindenburg Line commenced, with the British Fourth Army (with British, Australian and American forces) attacking in the Battle of St Quentin Canal and the French First Army attacking fortifications outside St Quentin. By 5 October, the Allies had broken through the entire depth of the Hindenburg defences over a front. General Rawlinson wrote, "Had the Boche not shown marked signs of deterioration during the past month, I should never have contemplated attacking the Hindenburg line. Had it been defended by the Germans of two years ago, it would certainly have been impregnable…."