Few people did as much to shape Canada’s Second World War effort, and no single person did as much to shape the Canadian army, as did General H.D.G. “Harry” Crerar. As chief of the general staff during the critical year and a half following the fall of France in June 1940, he was the primary architect of First Canadian Army, established the conditions for the army’s training and expansion, and advised the government to dispatch troops to Hong Kong. As a corps commander, he campaigned for Canadian involvement in the Dieppe raid. And, by 1944, he had assumed command of the army, eventually leading a combined Commonwealth army—the largest ever commanded by a Canadian—during the Rhineland offensive. His views on the form Canada’s military contribution should take became policy, even though many opposed them, including Prime Minister Mackenzie King.

Crerar’s achievements (and failures) are explainable, in part, by the nature of the crisis facing Canada and the Commonwealth during the Second World War. Nazi Germany was on the verge of victory in the summer of 1940 and the logic of that situation seemed to dictate, at least in hindsight, that Canada, united in the face of this clear threat to national survival, indeed to western civilization, commit itself to an all-out war effort. From that starting point, Canada’s military effort—a full field army (First Canadian Army) and at war’s end, the third largest navy and the fourth largest air force—seemed logical. But there was nothing predetermined about Canada’s war effort. In the words of a recent critical review of a book on the “fateful choices” made that summer, “more than most periods in history, the summer of 1940 was pregnant with a veritable brood of…plausible futures.”1