4th Battalion, Royal Australian Regiment

4th Battalion, The Royal Australian Regiment (4RAR) was raised at Woodside on 1 February 1964. The first regular infantry battalion to be raised in Australia, 4RARA served in Malaysia as part of the Far East Strategic Reserve from August 1965 to September 1967. Upon its return the battalion began training for service in Vietnam.

4RAR relieved 2RAR on 1 June 1968. It was based at Nui Dat, Phuoc Tuy province. V3 and W1 Companies from the Royal New Zealand Infantry Regiment (RNZIR) joined the battalion and on 2 June it was formally renamed 4RAR/NZ (ANZAC) Battalion.

On 23 June the battalion joined Operation Toan Thang II (13 June-18 July) on the Bien Hoa-Long Binh border. It then operated patrols through Phuoc Tuy. 4RAR/NZ was deployed to the Long Khanh-Bien Hoa border on 15 September, as part of Operation Hawkesbury (12-24 September). Through patrols, ambushes, and searches, the battalion was able to disrupt Viet Cong activity in the area and deny them access to supplies. The battalion returned to Nui Dat on 24 September.

4RAR/NZ returned to the Long Khanh-Bien Hoa border for Operation Goodwood (3 December-19 February) on 27 December. Goodwood was a reaction to an increase in Viet Cong activity that suggested an offensive was being planned. The battalion carried out patrols and reconnaissance. It was engaged in this operation until 19 February, having a brief respite at Nui Dat from 13 January to 7 February. On 19 February the battalion joined Operation Federal (17 February-2 April) in the Bien Hoa province, leaving the operation on 24 March. On 8 April the battalion began Operation Overlander (8-17 April) in the Bien Hoa province. It returned to Phuoc Tuy on 17 April.

The battalion was replaced by 6RAR on 1 May and departed for Australia on 19 May. In between operations, the battalion underwent training exercises. It returned to Vietnam in May of 1971, relieving 2RAR.

4RAR/NZ continued with pacification operations in Phuoc Tuy. The 1st Australian Task Force had adopted a "pacification programme" as its first priority in April 1969. This involved seeking out and destroying the enemy in its base areas, preventing enemy access to the civilian population, and helping to create a secure climate for South Vietnamese social, political, and military life. This work was demanding, dangerous, and monotonous for the troops. It was the primary task carried out by the battalion during its second tour.

The last battles fought by Australians in Vietnam occurred during Operation Ivanhoe (18 September-2 October 1971). Intelligence reports had alerted 4RAR/NZ to the presence of North Vietnamese Army (NVA) troops in northern Phuoc Tuy. The battalion engaged the troops and became involved in heavy fighting. Although it sustained comparatively high casualties during these engagements, 4RAR/NZ was successful in hindering NVA attempts to move further south.

The withdrawal of Australian forces from the area cut short 4RAR/NZ's tour. It completed eight of its twelve-month tour and was the last Australian battalion to leave Vietnam. On 7 November 1971 it withdrew from Nui Dat to Vung Tau, before departing for Australia on 8 December.