became for the first time in many years a participant, and in the course of time a very important one, in a vast European war, at first with a small expeditionary force and afterwards with an army comparable in strength with those of the Great Powers of continental Europe. In the process of building up this army the British tradition of centuries was abandoned and conscription was adopted.
Canada proceeded in a similar way—from the sending of a small contingent to the formation of an army much larger than the regular army with which Great Britain began the war.
This Canadian participation was a development of Canadian history, and of the history of Europe and of the British Empire. Take by way of contrast the Crimean War. Technically, Canada was then at war as part of the British Empire. But Canada played practically no part, partly because of its weakness, and partly because the war was really a local affair and not an earth-shaking conflict. Canada sent contingents to the South African War, but this again was a local conflict of comparatively small proportions, with a country having no outlet to and consequently no strength on the sea.
When the great European war broke out the saying that when the Empire is at war Canada is at war became not a mere legal doctrine but a living fact. And this was the first and most obvious cause of Canada's entrance into the war—namely, her relation to the rest of the Empire. It was taken for granted that Canada was at war. The question was as to the extent of her participation and the kind and amount of the force which she would contribute to the common cause. Yet this was not a matter of detail, but vital. The difference between sending 50,000 men and sending 500,000 was all-important. And it is in regard to this difference that we have to seek the reasons for Canada's decision.
The most potent cause was probably British sentiment —family sentiment—the sentiment founded upon race and tradition; the other cause may be called cosmopolitan