[1] On 10 April 1885, the 57th Battalion of Infantry Peterborough Rangers mobilized a company for active service with The Midland Battalion where it served in the Alberta Column of the North West Field Force.
[1][7] On 10 August 1914, the 2nd Battalion (Eastern Ontario Regiment), CEF was authorized for service and on 26 September 1914, the battalion embarked for Great Britain as part of the First Contingent of the Canadian Expeditionary Force.
After its arrival in the UK, the battalion provided reinforcements to the Canadian Corps in the field.
[2] On 12 March 1920, as a result of the Otter Commission and the following post-war reorganization of the militia, the 57th Regiment Peterborough Rangers was redesignated as The Peterborough Rangers and was reorganized with three battalions (two of them paper-only reserve battalions) to perpetuate the assigned war-raised battalions of the Canadian Expeditionary Force.
[1][3][8] As a result of the 1936 Canadian Militia reorganization, on 15 December 1936, The Peterborough Rangers was amalgamated with the 3rd Prince of Wales' Canadian Dragoons and the Headquarters and C Company of the 4th Machine Gun Battalion, CMGC, to form The Prince of Wales Rangers (Peterborough Regiment) – now the 50th Field Artillery Regiment (The Prince of Wales Rangers), RCA (on the Supplementary Order of Battle since 1970).