Henry Duncan Graham Crerar, born in Hamilton, Ontario, on April 28th, 1888; died in Ottawa on April 1st, 1965. Canadian Army officer and diplomat.

General H.D.G. Crerar. Department of National Defence / National Archives of Canada, PA-166584.

Harry Crerar was educated at the Royal Military College in Kingston, Ontario, from 1906 to 1909 and joined the Militia in the years preceding WWI. During the war, he served with distinction as a Canadian Field Artillery officer on French and Flanders battlefields, being awarded the Distinguished Service Order. When hostilities came to an end, Crerar was a lieutenant colonel of the Canadian Corps' General Staff.

Back in Canada, Crerar opted for a military career and joined the Permanent Force as Staff Officer Artillery in Ottawa. In 1923, he matriculated at the Camberley Staff College in England. Upon graduating, rather than returning to Ottawa, he accepted a posting as General Staff Officer 2 with the War Office in London. In 1929, Crerar was appointed General Staff Officer 1 at the National Defence HQ in Ottawa, and started working on a major reorganization of the Canadian Militia.

In 1934, Crerar was once again in Great Britain, following courses at the Imperial Defence College in London. Back to NDHQ, he became Director of Military Operations and Intelligence. He had then a reputation of being a brilliant mind and was perceived as the best officer on the Canadian General Staff. In March 1939, after serving a few months as Commander of the Royal Military College, Crerar was recalled to Ottawa to prepare a mobilization plan, as the possibility of another war increased.

As WWII began, Crerar was posted in London as Brigadier General Staff at the Canadian Military Headquarters. He was responsible for ensuring that the required equipment, barracks and training plans were in place when Canadian troops arrive. In July 1940, he was called back to Ottawa as Vice-Chief General Staff, but promoted a few days later to Chief General Staff by Defence Minister J.L. Ralston. He took immediate measures to improve the efficiency of National Defence HQ and set up emergency recruitment and training programmes for territorial defence, as volunteers were already pouring in, the National Resources Mobilization Act having been adopted on June 21st, 1940. He also put together a training programme for officers and soldiers slated to serve overseas.

Crerar returned to England, where, on December 23rd, 1941, he was appointed General Officer Commanding, I Canadian Corps. He would, therefore, find himself right in the middle of the crisis that followed the Dieppe raid on August 19th, 1942, since the Canadian troops that took part in that ill-fated operation were with I Canadian Corps. No Canadian officer had his say in the planning and Crerar's only option was to try to rationalize the losses and draw lessons from the failure.

Crerar lacked battlefield experience and thought he would have an opportunity to gain some as I Canadian Corps joined the 1st Canadian Infantry Division in Italy in October 1943. His hopes did not materialize, being recalled to England as soon as March 1944, to take over the command of the 1st First Canadian Army, replacing General McNaughton.

The 1st Canadian Army was mustered in Normandy on July 23rd, 1944, and, under Crerar's command, played a major role as the Allies circled German troops in the Falaise Gap in August 1944. Ill health forced Crerar to be replaced temporarily by Major-General Guy Simonds during the Battle of the Scheldt (October-November 1944). In February 1945, the 1st Canadian Army, with Crerar back at the helm, was once more on the front line. During the Rhineland campaign, he found himself at the head of a 450,000-men strong army, including allied units under 1st Canadian Army command.

Crerar retired from the military in 1946. Later, he occupied diplomatic postings in Czechoslovakia, the Netherlands and Japan.

Harry Crerar was an outstanding General Staff officer. He left his mark on the largest army Canada ever levied, structuring the HQ, organizing training for the troops that were to join its ranks, and commanding the 1st Army during the last major campaigns. After the war, he was the one in charge of the demobilization process.