[1][2][3][4] On 10 April 1885, the 40th Northumberland Battalion of Infantry mobilized a company for active service with The Midland Battalion where it served in the Alberta Column of the North West Field Force.
After its arrival in the UK, the battalion provided reinforcements to the Canadian Corps in the field.
After its arrival in the UK, on 6 October 1916, the battalion's personnel were absorbed by the 36th Reserve Battalion, CEF to provide reinforcements to the Canadian Corps in the field.
[2] Lieutenant Wallace Lloyd Algie was posthumously awarded the VC for actions on 11 October 1918, near Iwuy, France, while serving with the 20th Battalion CEF.
On 15 March 1920, as a result of the Otter Commission and the following post-war reorganization of the militia, the 40th Northumberland Regiment was redesignated as The Northumberland (Ontario) Regiment and was reorganized with two battalions (one of them a paper-only reserve battalion) to perpetuate the assigned war-raised battalions of the Canadian Expeditionary Force.