After arriving in France in March, the battalion moved to the Western Front, occupying the forward positions around Armentières in northern France on 10 April 1916.
In mid-July, the battalion was transferred to the Somme, where they subsequently took part in the Battles of Pozières and Mouquet Farm, during which they suffered almost 90 per cent casualties.
In early 1917, the Germans shortened their lines and withdrew to the Hindenburg Line and the Australian divisions in the Somme were ordered to carry out an advance to follow them up.
After being reinforced, the 23rd Battalion was committed to the fighting at the Second Battle of Bullecourt in early May 1917 after the first attempt to capture the town by the 4th Australian Division failed.
Succeeding in capturing all its objectives, it was heavily counter-attacked by German forces, suffering a large number of casualties, including 100 men killed or died of wounds before being relieved by the Australian 3rd Battalion.
After this the battalion was withdrawn from the line until early September 1917 when they moved into positions around Ypres, Belgium, and participated in the Battle of Broodseinde on 4 October.
During this battle, the 6th Brigade was positioned to the south of Zonnebeke Lake, and the 23rd Battalion lost three officers and 101 other ranks killed or wounded, some of which were inflicted when an intense German mortar barrage fell upon their "waiting line" prior to the attack.
Nevertheless, the attack which followed, after overcoming an encounter with a German regiment, the 212th, in no man's land, resulted in success as the Australians captured the ridge.

In early 1918, Russian resistance on the Eastern Front collapsed in the wake of the October Revolution and, as a result, the Germans were able to transfer a large number of troops to the Western Front.
This greatly improved the German strength in the west and, as a result, in March, they launched their Spring Offensive.
With the Germans making rapid gains, many Australian units, including the 23rd Battalion, were thrown into the line to blunt the attack in early April, as the 6th Brigade relieved the 12th around Dernancourt.
After the German offensive was halted, a brief lull followed during which the Allies sought to regain the initiative, launching a series of "Peaceful Penetration" operations.
Following this, the 23rd participated in the fighting at Hamel on 4 July, advancing as the right-hand battalion on the southern front behind a devastatingly accurate preparatory barrage.
On 8 August 1918, the 23rd joined the Allied Hundred Days Offensive, which was launched at Amiens, and was followed by a series of advances followed as the Allies began advancing through the Somme.
For his actions during the fighting at Mont St. Quentin in early September, one of the battalion's soldiers, Private Robert Mactier, was awarded the Victoria Cross posthumously.
After participating in the Battle of Beaurevoir between 3 and 4 October, the battalion was sent to the rear for rest when the units of the Australian Corps, severely depleted, were withdrawn from the line upon the insistence of the Australian prime minister, Billy Hughes.
As a result, it took no further part in the fighting before the armistice was declared on 11 November.

Following the end of hostilities, the demobilisation process began and slowly the battalion's numbers began to dwindle as its personnel were repatriated back to Australia and returned to civilian life.
The 23rd Battalion was disbanded in Belgium on 30 April 1919.
Throughout its service during the war, it suffered 686 killed and 2,317 wounded (including gassed).
For its involvement during the war, the 23rd Battalion received a total of 19 battle honours; these were bestowed upon the battalion in 1927.
After arriving in France in March, the battalion moved to the Western Front, occupying the forward positions around Armentières in northern France on 10 April 1916. In mid-July, the battalion was transferred to the Somme, where they subsequently took part in the Battles of Pozières and Mouquet Farm, during which they suffered almost 90 per cent casualties. In early 1917, the Germans shortened their lines and withdrew to the Hindenburg Line and the Australian divisions in the Somme were ordered to carry out an advance to follow them up. After being reinforced, the 23rd Battalion was committed to the fighting at the Second Battle of Bullecourt in early May 1917 after the first attempt to capture the town by the 4th Australian Division failed. Succeeding in capturing all its objectives, it was heavily counter-attacked by German forces, suffering a large number of casualties, including 100 men killed or died of wounds before being relieved by the Australian 3rd Battalion. After this the battalion was withdrawn from the line until early September 1917 when they moved into positions around Ypres, Belgium, and participated in the Battle of Broodseinde on 4 October. During this battle, the 6th Brigade was positioned to the south of Zonnebeke Lake, and the 23rd Battalion lost three officers and 101 other ranks killed or wounded, some of which were inflicted when an intense German mortar barrage fell upon their "waiting line" prior to the attack. Nevertheless, the attack which followed, after overcoming an encounter with a German regiment, the 212th, in no man's land, resulted in success as the Australians captured the ridge.
In early 1918, Russian resistance on the Eastern Front collapsed in the wake of the October Revolution and, as a result, the Germans were able to transfer a large number of troops to the Western Front. This greatly improved the German strength in the west and, as a result, in March, they launched their Spring Offensive. With the Germans making rapid gains, many Australian units, including the 23rd Battalion, were thrown into the line to blunt the attack in early April, as the 6th Brigade relieved the 12th around Dernancourt. After the German offensive was halted, a brief lull followed during which the Allies sought to regain the initiative, launching a series of "Peaceful Penetration" operations. Following this, the 23rd participated in the fighting at Hamel on 4 July, advancing as the right-hand battalion on the southern front behind a devastatingly accurate preparatory barrage. On 8 August 1918, the 23rd joined the Allied Hundred Days Offensive, which was launched at Amiens, and was followed by a series of advances followed as the Allies began advancing through the Somme. For his actions during the fighting at Mont St. Quentin in early September, one of the battalion's soldiers, Private Robert Mactier, was awarded the Victoria Cross posthumously. After participating in the Battle of Beaurevoir between 3 and 4 October, the battalion was sent to the rear for rest when the units of the Australian Corps, severely depleted, were withdrawn from the line upon the insistence of the Australian prime minister, Billy Hughes. As a result, it took no further part in the fighting before the armistice was declared on 11 November.
Following the end of hostilities, the demobilisation process began and slowly the battalion's numbers began to dwindle as its personnel were repatriated back to Australia and returned to civilian life. The 23rd Battalion was disbanded in Belgium on 30 April 1919. Throughout its service during the war, it suffered 686 killed and 2,317 wounded (including gassed). For its involvement during the war, the 23rd Battalion received a total of 19 battle honours; these were bestowed upon the battalion in 1927.
23rd Battalion (Australia)