On 26 March 1916, he embarked on the HMT Maryland for Marseilles, France, along with 35 other troops and 74 horses.
While stationed at Sailly  in France, he was commissioned to the rank of Major on 12 May 1916, at the age of 21, the youngest Major in the AIF.

In late July 1916, he fought at the Battle of Pozières (part of the Battle of the Somme), for which he was awarded the Distinguished Service Order (19 August 1916).
He was chosen (together with Colonel J.A. "Reg" Robinson) to represent the first AIF at an award ceremony in Buckingham Palace.
He received the DSO from George V. The DSO was:
For conspicuous gallantry and ability during a period of operations under very heavy shell fire.
 The good work done by his company was due to his untiring energy and fine powers of leadership
In September 1917, he fought in the Third Battle of Ypres (the Battle of Passchendaele).
For this he was mentioned in dispatches.
In the weeks leading up to the conflict, there was a great deal of preparation for the possibility of mustard gas attack: an instruction in gas drill and numerous gas drills.
Gas-proof doors and windows were installed as they did engineering works on buildings.
The preparations proved to be necessary: there were nerve gas attacks on five different occasions in March 1918.
On 21 March 1918, the war diary records:
Gas alarm early morning.
The locality was again subjected to a heavy gas and shell bombardment, which lasted for over 3 hours.
The gas guard dropped anti-gas curtains at both entrances and warned all ranks, including those living outside.
Gas entered the tunnel from the rear.
This was caused by a large gas shell bursting at the mouth of the first tunnel in rear ... Box respirators were worn from 1/2 to 2 hours.

In August 1918 Savage fought in the Battle of Amiens.
He was stationed at Vaire-sous-Corbie in the Picardy region.

On three occasions it was recommended that he be promoted to colonel, but he was considered too young.
On 26 March 1916, he embarked on the HMT Maryland for Marseilles, France, along with 35 other troops and 74 horses. While stationed at Sailly  in France, he was commissioned to the rank of Major on 12 May 1916, at the age of 21, the youngest Major in the AIF.
In late July 1916, he fought at the Battle of Pozières (part of the Battle of the Somme), for which he was awarded the Distinguished Service Order (19 August 1916). He was chosen (together with Colonel J.A. "Reg" Robinson) to represent the first AIF at an award ceremony in Buckingham Palace. He received the DSO from George V. The DSO was:
For conspicuous gallantry and ability during a period of operations under very heavy shell fire.  The good work done by his company was due to his untiring energy and fine powers of leadership
In September 1917, he fought in the Third Battle of Ypres (the Battle of Passchendaele). For this he was mentioned in dispatches. In the weeks leading up to the conflict, there was a great deal of preparation for the possibility of mustard gas attack: an instruction in gas drill and numerous gas drills. Gas-proof doors and windows were installed as they did engineering works on buildings. The preparations proved to be necessary: there were nerve gas attacks on five different occasions in March 1918. On 21 March 1918, the war diary records:
Gas alarm early morning. The locality was again subjected to a heavy gas and shell bombardment, which lasted for over 3 hours. The gas guard dropped anti-gas curtains at both entrances and warned all ranks, including those living outside. Gas entered the tunnel from the rear. This was caused by a large gas shell bursting at the mouth of the first tunnel in rear ... Box respirators were worn from 1/2 to 2 hours.
In August 1918 Savage fought in the Battle of Amiens. He was stationed at Vaire-sous-Corbie in the Picardy region.
On three occasions it was recommended that he be promoted to colonel, but he was considered too young.
Percival Savage