 Born in Queensland to a farming family, Towner enlisted in the Australian Imperial Force in 1915. Posted to the transport section of the 25th Battalion, he served in Egypt until his unit was sent to the Western Front. He then transferred to the 2nd Machine Gun Battalion where he was commissioned as a lieutenant and twice mentioned in despatches for his leadership. During June 1918, Towner led a machine gun section in attack near Morlancourt and assisted the infantry in reaching its objectives under heavy fire, for which he was awarded the Military Cross. In September, again commanding a machine gun section, he was involved in the Allied counteroffensive that broke the German lines at Mont St. Quentin and Péronne. Fighting for thirty hours after being wounded, his "conspicuous bravery, initiative and devotion to duty" earned him the Victoria Cross, which was presented by King George V in April 1919.
