The 4th Battalion, Canadian Mounted Rifles was authorized on 7 November 1914 as the 4th Regiment, Canadian Mounted Rifles, CEF and embarked for Britain on 18 July 1915. It disembarked in France on 24 October 1915, where it fought as part of the 2nd Brigade Canadian Mounted Rifles until 31 December 1915, when it was converted to infantry and allocated to the 8th Infantry Brigade, 3rd Canadian Division. The regiment was redesignated the 4th Battalion, Canadian Mounted Rifles, CEF on 1 January 1916 and was disbanded on 6 November 1920.
The battalion recruited in Militia District 2 in Ontario and was mobilized at Toronto, Ontario.
The battalion had four Officers Commanding:Lt.-Col. S.F. Smith, 18 July 1915 – 6 March 1916
Lt.-Col. J.F.H. Ussher, 6 March 1916 – 3 June 1916
Lt.-Col. H.D.L. Gordon, DSO, 7 June 1916 – 27 May 1917
Lt.-Col. W.R. Patterson, DSO, 28 May 1917-Demobilization
One member of the battalion, Pte Thomas William Holmes, won the Victoria Cross for his actions on 26 October, 1917 during the Battle of Passchendaele. Pte Holmes, then 19, is Canada's youngest Victoria Cross winner.
The battalion was awarded the following battle honours:MOUNT SORREL
ARRAS, 1917, '18
Canal du Nord
FRANCE and FLANDERS, 1915-18
The 4th Battalion, Canadian mounted rifles is perpetuated by The Governor General's Horse Guards.