 A formal assault plan, adopted in early March 1917, drew heavily on the briefings of staff officers sent to learn from the experiences of the French Army during the Battle of Verdun.For the first time the four Canadian divisions would fight together.The nature and size of the attack needed more resources than the Canadian Corps possessed; the British 5th Division, artillery, engineer and labour units were attached to the corps, bringing the nominal strength of the Canadian Corps to about 170,000 men, of whom 97,184 were Canadian.