Formed as an armoured unit in the Australian Regular Army on 7 July 1949, the regiment squadrons served during the Vietnam War operating Centurion tanks.

More recently the regiment has contributed small groups and individuals to operations in East Timor, Iraq, Afghanistan, the Solomon Islands and elsewhere.

[5] Due to the perceived unsuitability of the Churchill and the late arrival of the new platform, the regiment was not deployed as part of Australia's commitment to the Korean War, although a number of officers served on exchange with British and US formations and the unit provided machine-gunners and signalers to Australian infantry battalions as reinforcements.

This was known as Nucleus Squadron and was based in Holsworthy, New South Wales, with the purpose of forming the basis of a second tank unit which was to be named the 2nd Armoured Regiment.

During the early stages of the war, the regiment had provided personnel to 1 Troop, A Squadron, 4th/19th Prince of Wales Light Horse, which was deployed on active service to South Vietnam in May.

In February 1968, C Squadron was sent to Vietnam, however, two of its four tank troops were initially held back until the Centurions had proved themselves capable of operating in the conditions.

[5] Meanwhile, in Australia, the regiment had again reached full strength in May, with A Squadron re-raised in order to meet the ongoing operational commitment.

[14] Over the next four years the regiment's squadrons provided invaluable close support to the infantry, particularly during the clearance of Viet Cong bunker systems.

[5] The Centurions were able to move through the countryside more easily than expected and although they were vulnerable to anti-tank weapons and mines, their firepower and shock action had a decisive effect on the battlefield.

[16] The infantry were this time supported by Centurion tanks which had been called forward by road from Nui Dat and had arrived just hours before Balmoral was subjected to a two battalion attack.

[5] On 6–7 June, B Squadron was involved in a fierce action during the Battle of Binh Ba, a village 5 kilometres (3.1 mi) north of Nui Dat.

Each time the infantry were fired on, the tanks would blast a hole in the wall of the building, through which small teams could then enter and clear the structure of any opposition.

The abolition of National Service after the end of Australian involvement in Vietnam depleted the regiments strength to the point where training was severely restricted until it was finally reinforced during 1974.

[22][21] From this time until the early 2010s the regiment was the only combat unit in Army which operated tanks, serving as the centre of excellence for armoured conventional warfare for the service.

[2][23][Note 2] With the value of heavy armour proven again during the Vietnam War, government endorsed the plan to replace the aged Centurion tank.

[25] On 21 April 1981, the Colonel-in-Chief of the RAAC, the Prince of Wales (now King Charles III), presented the unit with its first Regimental Standard.

[2] The other elements of 1st Brigade would relocate to Darwin by the end of the decade resulting in all the units consolidating in a single location for the first time.

In this period small groups and individuals of the regiment served on Operation Relex on border protection tasks, in East Timor, Bougainville, Sinai and the Solomon Islands.

[27] The regiment's current standard was presented by the then Governor General, Dr. Peter Hollingworth on 13 July 2002, at a mounted parade held in Darwin.

[2] While some efforts had been made to improve crew conditions on the Leopard in the late 1990s and enhance its night fighting capability, the lack of upgrades to it had rendered it obsolete by the early 2000s.

With a change in government policy articulated in the 2000 Defence White Paper, the September 11 attacks and the subsequent invasion of Iraq in 2003, momentum built to replace the Leopard tank.

Following government direction and a rapid acquisition, after 30 years of service the Leopard was replaced by 59 M1A1 Abrams Integrated Management Situational Awareness (M1A1 AIM SA) main battle tanks, with the occasion marked by a mounted parade on 26 July 2007.

[23][30] These included as Bushmaster PMV crews within the various rotations of the Al Muthanna Task Group and Overwatch Battle Group-West, trainers as part of the Australian Army Training Team-Iraq and as embedded staff and advisors within various headquarters under the auspices of Operation Catalyst.

Under the later Operation Okra members would again serve as trainers and advisors within Task Group Taji to help build the capacity of the Iraqi Security Forces.

[41] On 27 October 2022, the Army Reserve A Squadron 3rd/9th Light Horse (South Australian Mounted Rifles) was allocated as a direct command sub-unit to 1st Armoured Regiment.

[42] However, following the change of government and publication of the Defence Strategic Review[43] in April 2023 the Army Objective Force structure was no longer considered viable.