The outbreak of the First World War in August 1914 saw a rapid and fervent response across Canada, and the 48th Highlanders of Canada were quick to answer the call. The Regiment contributed a full battalion, the 15th Battalion (48th Highlanders of Canada), to the First Canadian Contingent, which departed for overseas service in October 1914. Notably, the soldiers were equipped in their distinctive uniforms, a testament to regimental pride and financial independence, as these were paid for by the Regiment itself. Beyond the initial contingent, the 48th Highlanders’ commitment to the war effort was profound, as they recruited and mobilized two additional reinforcement battalions, the 92nd and the 134th, ensuring a continuous flow of dedicated men to the front lines.

The 15th Battalion’s baptism of fire came in one of the most terrifying and pivotal moments of the war: the Second Battle of Ypres. On April 24, 1915, just a couple of months after arriving in Belgium, they faced the brutal reality of modern warfare when they were subjected to the first large-scale chlorine gas attack. Amidst the chaos and devastation, the 48th Highlanders were given a stark order: to hold their ground to the last man. They held steadfastly, displaying immense courage and unwavering resolve in the face of this unprecedented horror. The cost was staggering; in that single engagement, the battalion suffered a catastrophic 664 casualties, including those killed, wounded, or taken prisoner, a profound loss that underscored their sacrifice and steadfastness.
Despite these immense losses, the 15th Battalion persevered through the grinding attrition of the Western Front until the very end of the war. Their service continued across the most infamous and brutal battlefields of the conflict, including the harrowing Somme offensive, the mud-soaked hell of Passchendaele, and the defining Canadian victory at Vimy Ridge. Their consistent bravery and tactical prowess earned the Regiment an impressive 21 Battle Honours, recognizing their exceptional contributions to key engagements. By the armistice, the 15th Battalion had borne a tremendous burden, with 1,625 Highlanders making the ultimate sacrifice, killed in action, a somber testament to their enduring legacy of courage and dedication.