The 4th Battalion of the Canadian Expeditionary Force was raised at Valcartier on 2 September 1914. 

Consisting of recruits from the 2nd Military District, which encompassed Aurora, Brampton, Brantford, Hamilton and Niagara Falls. 

After landing in France on 11 February 1915, the battalion was assigned to the 1st Canadian Infantry Brigade, which was part of the 1st Canadian Division. After being committed to the fighting, casualties mounted and the original members of the battalion were later reinforced by the 3rd Canadian Reserve Battalion. 

At the conclusion of hostilities, the 4th Battalion sailed to the United Kingdom on 23 March 1919, before proceeding across the Atlantic. They disembarked in Canada on 21 April 1919. 

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