Attached to the 5th Brigade, 2nd Division, the battalion was raised in 1915 and sent to Egypt initially, before taking part in the fighting at Gallipoli against the Turks.

[1] When World War I began, due to the provisions of the Defence Act 1903 which precluded sending conscripts overseas to fight, it became necessary to raise an all volunteer force, separate to the militia, for service in the Middle East and Europe.

In May 1915, the battalion left Australia and after spending some time in Egypt training, they landed at Anzac Cove on 20 August 1915.

A period of respite followed after this, as the 17th was moved north to Belgium along with the rest of the 2nd Division, remaining there until October when they were transferred back to the Somme.

During this time they were involved in the battles at Amiens and Mont St Quentin in August, before participating in the attack on the "Beaurevoir Line" at Montbrehain in October.

The Australian government then decided to reorganise the units of the Citizen Forces (later known as the "Militia") to perpetuate the divisional structure, numerical designations and battle honours of the AIF.

[9] During the inter-war years, the battalion was assigned to the 8th Brigade, which was headquartered in North Sydney and formed part of the 2nd Military District.

[10] During World War II the battalion undertook garrison duties in Australia, as part of the 9th Brigade, based in New South Wales.

[12] Although there were reductions among the home forces as the war progressed, the 17th Battalion remained on the Australian order of battle until 6 April 1944 when it was disbanded,[9] having not seen active service during World War II, as the Australian Army sought to reallocate manpower back to industry or to other units that were engaged in combat operations in the Pacific.

This lasted until 1987 when another reorganisation of the Australian Army Reserve led to the unit's amalgamation to form the 2nd/17th Battalion, Royal New South Wales Regiment.