After a short period of training it was committed to the fighting on the Western Front, remaining in France and Belgium until the war ended.

Consisting of recruits from the 2nd Military District, which encompassed Aurora, Brampton, Brantford, Hamilton and Niagara Falls, the battalion's first commanding officer Lieutenant-Colonel W.S.

[2] Within several weeks of its formation, the battalion embarked at Quebec on 3 October 1914 aboard the transport Tyrolia, bound for the United Kingdom.

The unit's personnel were subsequently demobilized in Toronto on 23 April 1919, and the battalion was disbanded officially on 15 September 1920.

[2] Throughout its involvement in the fighting on the Western Front, the 4th Battalion took part in the following battles: Ypres (1915) Passchendaele (1917); Gravenstafel; St. Julien; Festubert (1915); Mount Sorrel; Somme (1916); Flers-Courcelette; Ancre Heights; Arras (1917); Vimy (1917); Arleux; Scarpe (1918); Hill 70; Passchendaele; Amiens; Drocourt-Quéant; Hindenburg Line; Canal du Nord; Pursuit to Mons.