From Wikipedia
For King And Empire
Episode Two
The next area where Canadians fought was at the Battle of the Somme from mid-September to mid-November. Initially launched as a campaign to relieve pressure from the beleaguered French forces at the Battle of Verdun, the Allied casualties actually exceeded those at Verdun. On July 1, 1916, the British launched the assault which resulted in the largest massacre of British forces - over 57,550 casualties in one day. Among them were 732 men from the 1st Newfoundland Regiment ; of the 801 men of the Newfoundland Regiment, only 68 men answered the regimental roll call after the attack. 255 were dead, 386 were wounded, and 91 were listed as missing. Every officer who had gone over the top was either wounded or dead. On the day that the British forces suffered their worst losses in history, the 1st Newfoundland Regiment also suffered its worst loss in its history.
As the fighting continued, the Canadians (with the support of a new 4th Canadian Division) were asked to secure the town of Courcelette. In the major offensive which began at dawn on September 15 the Canadian Corps, on the extreme left of the attack, assaulted on a 2,200-yard sector west of the village of Courcelette. By November 11th, the 4th Canadian Division finally secured most of the German trenches in Courcelette and then rejoined the Canadian Corps at Vimy Ridge.
The Battle of the Somme claimed 24,029 Canadian casualties. But it also gave Canadian units the reputation of a formidable assault force. As Prime Minister Lloyd George wrote, "The Canadians played a part of such distinction that thenceforward they were marked out as shock troops; for the remainder of the war they were brought along to head the assault in one great battle after another. Whenever the Germans found the Canadian Corps coming into the line they prepared for the worst."

Canadian POWs. February 1916.