History - During the Great War

Within a week of the declaration of the Great War, the Regiment contributed the first Commanding Officer, 11 officers and 357 Non-commissioned Officers and men to the newly-formed 'Royal Montreal Regiment' (14th Bn CEF). Further contingents were provided to the PPCLI, 13th Bn (RHC), 23rd Bn (RMR), 24th Bn (VRC), and 60th Bn (VRC), all of the CEF.

Lieutenant-Colonel Meighen returned from overseas command of the 14th Bn in June, 1915, and announced in September that permission finally had been given to raise an overseas battalion of the Regiment, the 87th Bn CEF.

Active recruiting began on 23 October, and in seven weeks the Battalion was raised and ready for its winter training in barracks at St Jean, Quebec. The Battalion was unique in that recruiting had occurred not only in Montreal but throughout Canada (rather than the restricted areas allocated to other CEF Battalions) - it was a thoroughly representative 'Canadian' unit. Use of the title Canadian Grenadier Guards was also different, as the policy had been to not send CEF Battalions overseas with their Militia titles; for the Canadian Grenadiers, special authority was sought from HE The Governor- General, HRH The Duke of Connaught (the Colonel, Grenadier Guards from 1904-42). He authorized additionally the wearing of Grenadier Guards' badges, and through the British Grenadiers, the attachment of an officer and four Drill Sergeants after arrival in England, whose purpose was to prepare the 87th Bn for service in France, and to inculcate Guards traditions within the Regiment.

The 87th Battalion entered France on 12 August, 1916, and remained on the continent until 1919. During the War, it earned 17 Honorary Distinctions, and Private J.F. Young was awarded the VC.

After the Battle of Vimy Ridge in April, 1917, the increasing difficulty of finding replacements for the English-speaking Battalions from Montreal became acute. (Earlier, the Regiment had raised a second CEF Battalion, the 245th Bn (CGG) which, although it had moved to England did not fight as a unit, its personnel being used to support the 87th Bn; additionally, the 87th Bn had provided earlier, in August, 1916, 300 Grenadiers to the 1st (Ontario) Bn, CEF). Consequently, and to retain the Canadian Grenadiers in the Order of Battle, the decision was made to transfer the remaining personnel of the 60th Bn (VRC) to the 87th Bn. On 22 November, 1918, HM King George V granted the title of 'Guardsman' to Private soldiers of the Brigade of Guards which distinction was extended to the Canadian Grenadiers.

On return to Canada in 1919, the 87th Bn was demobilized; its name was perpetuated by the 1st Battalion, The Canadian Grenadier Guards (87th Bn CEF) in 1920. At the same time the 2nd Battalion, Canadian Grenadier Guards (245th Bn CEF) perpetuated the other Great War Battalion of the CEF. With this reorganization, the Regiment lost the ordinal title of 'First Regiment', as numerals for all Regiments (except the R22eR) were discarded.

In 1911, Lieutenant-Colonel J.W. Carson (later Major General Sir William Carson) was asked to reorganize the Regiment to which he agreed on the conditions that he be given a free hand in the selection of his officers; that the Regiment should be renamed and become a Regiment of Foot Guards whilst still preserving its identity as the First Regiment of the Active Militia of Canada; and that it should be provided with an armoury of its own. The reorganization was promulgated in January, 1912, when the First Regiment became 1st Regiment, "The Grenadier Guards of Canada", and in April, 1914, took possession of the new Armoury and changed its name again to 1st Regiment Canadian Grenadier Guards. It remained the First Regiment (although junior as a Regiment of Foot Guards to the Governor General's Foot Guards, raised in 1872 as Household Troops for the Governor-General), and was seen to be the Canadian unit of Household Troops for the Sovereign.