Towner enlisted in the
Australian Imperial Force on 4 January 1915. Assigned to the transport section of the
25th Battalion as a
private, he embarked aboard HMAT
Aeneas from
Brisbane on 29 June, bound for Egypt. The troopship arrived in August, and the battalion spent the rest of the month training in the desert before transferring to the
Gallipoli Peninsula. Towner, however, remained in Egypt with the army's transportation elements. the unit was the first Australian battalion to arrive in France. his service with his transport section earned him praise for his "devotion to duty and consistent good work", and on 9 April he was
Mentioned in the Despatches of
Field Marshal Sir Douglas Haig. Towner was granted leave to the United Kingdom in January 1918. On the night of 10/11 June 1918, Towner was in command of a machine gun section during an attack to the south of
Morlancourt. One of the first to reach the objective, he deployed his section and got its guns into action "very quickly". By using captured German machine guns he was able to increase his section's fire
Victoria Cross On 1 September 1918, Towner was in command of No. 3 Section of the 7th Machine Gun Company during an attack on
Mont St Quentin, near
Péronne. the section was attached to the right flank of the 24th Australian Infantry Battalion, whose principal objective was to seize the summit of Mont St Quentin. To accomplish this, the battalion would have to advance through the village of Feuillaucourt before moving down to the Péronne road. The Australians began their advance at 06:00 behind an artillery screen, with Towner's section covering a front of . Eventually the Australian infantry were forced to retire a short distance, but with all its crew having become casualties, one gun was left behind. Alone, Towner dashed out over
no man's land and retrieved the weapon. With this gun he "continued to engage the enemy whenever they appeared", putting a German machine gun out of action with his accurate fire. Initially admitted to the 41st Casualty Clearing Station, he was transported by train to the 2nd
Red Cross Hospital at
Rouen.
Later war service Following his recuperation, Towner was granted three weeks' leave to England from 14 September 1918. He rejoined his unit on 12 October and, for six days, was attached to the School of Instruction. Following thirteen days' leave in France during late November, he returned again to the 2nd Machine Gun Battalion on 12 December. On 10 April 1919, Towner attended an investiture ceremony in the ballroom of
Buckingham Palace, during which he was decorated with his Victoria Cross and Military Cross by
King George V. Three weeks later he boarded HT
Karagola, bound for Australia. Disembarking at
Sydney on 14 June 1919 he made his way to Brisbane, and was discharged from the Australian Imperial Force on 16 August 1919. ==Later life==