After World War II, the Australian military was demobilised.
By 1948 this process had been completed and a period of reorganisation began.
This resulted in the establishment of a Regular infantry force consisting of a single brigade and two divisions of part-time soldiers in the Citizens Military Force (CMF).
There was no room within this structure for the 1st Division and as a result it remained off the Australian Army's order of battle until 1960, when its headquarters was reformed in Sydney, New South Wales, following the implementation of the Pentropic divisional structure, commanding all Army units – Regular and CMF – in New South Wales.
It was also responsible for training some CMF units in other states.

In 1965, the Pentropic structure was abolished and the divisional headquarters' was tasked with determining the readiness of units deploying to Vietnam.
It fulfilled this role until Australia's commitment to the conflict ended in late 1972.
In November the following year, the division was established at Enoggera Barracks in Brisbane, Queensland, and was re-formed as the Australian Army's "main striking force".
Throughout the Cold War era, the division grew into a formation of over 13,000 personnel, which, at its peak in the early 2000s consisted of four brigades: two Regular, one integrated and one Reserve spread across Queensland, New South Wales and the Northern Territory.
In 1997, the formation's headquarters assumed the additional task of raising a deployable joint force headquarters, tasked with commanding Army, Royal Australian Air Force and Royal Australian Navy assets during large-scale operations.

During this time, the division was not deployed as a complete formation, although its elements undertook numerous operations.
These include peacekeeping operations in Namibia, Western Sahara, Cambodia, Somalia, Rwanda, East Timor, and the Solomon Islands.
The division also deployed personnel to Iraq as part of Operation Catalyst and to Afghanistan as part of Operation Slipper.
After World War II, the Australian military was demobilised. By 1948 this process had been completed and a period of reorganisation began. This resulted in the establishment of a Regular infantry force consisting of a single brigade and two divisions of part-time soldiers in the Citizens Military Force (CMF). There was no room within this structure for the 1st Division and as a result it remained off the Australian Army's order of battle until 1960, when its headquarters was reformed in Sydney, New South Wales, following the implementation of the Pentropic divisional structure, commanding all Army units – Regular and CMF – in New South Wales. It was also responsible for training some CMF units in other states.
In 1965, the Pentropic structure was abolished and the divisional headquarters' was tasked with determining the readiness of units deploying to Vietnam. It fulfilled this role until Australia's commitment to the conflict ended in late 1972. In November the following year, the division was established at Enoggera Barracks in Brisbane, Queensland, and was re-formed as the Australian Army's "main striking force". Throughout the Cold War era, the division grew into a formation of over 13,000 personnel, which, at its peak in the early 2000s consisted of four brigades: two Regular, one integrated and one Reserve spread across Queensland, New South Wales and the Northern Territory. In 1997, the formation's headquarters assumed the additional task of raising a deployable joint force headquarters, tasked with commanding Army, Royal Australian Air Force and Royal Australian Navy assets during large-scale operations.
During this time, the division was not deployed as a complete formation, although its elements undertook numerous operations. These include peacekeeping operations in Namibia, Western Sahara, Cambodia, Somalia, Rwanda, East Timor, and the Solomon Islands. The division also deployed personnel to Iraq as part of Operation Catalyst and to Afghanistan as part of Operation Slipper.
1st Division (Australia)