In 1917, the British wanted to destroy U-boat bases on the Belgian coast before the Germans could mount a blockade that would cripple Allied efforts. Capturing the ridge at Passchendaele, the highest point in the area, would give them an advantage.
The Canadian Corps, which had fought in a dozen battles after its success capturing Vimy Ridge in April, was ordered in October 1917 to help capture the ridge at Passchendaele.
The objections of their commander, Lieutenant-General Sir Arthur Currie, were ignored. Months of fighting and unrelenting rain had turned the area into a muddy bog in which men and horses drowned. The stench of unburied bodies seemed to underscore the futility of the task. He estimated 16,000 Canadian lives would be lost in the attempt; the total was 15,654.