At the beginning of August 1918, the combined weight of the Allies, now including American forces, began the final advance against the German forces.

In May 1918, the 20th Hussars as part of the 5th Cavalry Brigade, were withdrawn to the area of Le Touquet for the summer where they rested, reorganised, played sports and trained. On 3rd August, while attending a race meeting, the Brigade were given orders to march the next day. The 20th moved at speed and at night to Cachy, east of Amiens, by 7th August.

The Second Battle of Amiens was launched against the Germans over a front of 11 miles (18 kms). A preliminary bombardment of 2,070 guns was followed up by an advance using a record number of tanks and sixteen divisions. The Royal Air Force, formed on 1st April that year, with its French counterpart worked with the artillery to pinpoint targets and to attack ground forces. The battle continued until 4th September by which time Germany had lost more than 100,000 casualties.