On 12 July 1915, Konowal enlisted in the 77th Canadian Infantry Battalion, and on 19 June 1916, left Halifax for Liverpool. After arriving in England, Konowal was promoted to acting corporal and was transferred to the 47th (British Columbia) Battalion of the 4th Canadian Division. In August 1916, the 4th Division arrived in France, and took part in the assault on Vimy Ridge in April 1917. From 22–24 August 1917, during the Battle of Hill 70 in Lens, France, he was recognized for conspicuous gallantry in the face of the enemy and awarded the Victoria Cross. Konowal's medal was personally presented by King George V, and he was promoted to sergeant.