After leaving Ypres, the Canadian Corps moved to the Somme valley to support the Allied forces, who were sustaining massive losses in their futile attempts to break through German lines. On 15 September 1916, three divisions of the Canadian Corps neutralized the German defences in the ruined French village of Courcelette. Several innovations helped the Canadian offensive, including walking behind the artillery barrage as it advanced across German lines, trapping the enemy soldiers in their dugouts until the Canadians were on top of them. Tanks were also used for the first time and, despite being slow and prone to breakdown, they crossed trenches and steamrolled through enemy lines. Attached to each tank were five infantry men, who removed casualties in the vehicle’s path. The Germans found the tanks terrifying and many immediately surrendered. Although the attack on Courcelette was a victory, several thousand Canadians lost their lives.