Topic: AIF & MEF & EEF
The Australian Military
Army Unit Numbering
The following article is extracted from Dennis, P. et. al., The Oxford Companion to Australian Military History, 2nd Edition, OUP, Melbourne, 2008, pp. 541-542.
Army Unit Numbering
During its existence the Army has used a variety of numbering systems to denote its units, which can be bewildering to both casual observer and determined scholar alike. Though numbers were frequently used by the colonial forces it was just as common for units, following British tradition, to adopt names, sometimes colourful and usually with a territorial association; the Victorian Rangers being but one example.
Despite some loud complaints about the trampling of traditions, the formation of the Commonwealth Military Forces in 1903 brought a new rationalised numbering system in which the units of New South Wales were allocated the first on offer, with units in the other states following on.
Thus the 1st through 6th Light Horse Regiments were raised in New South Wales, the 7th through 11th were found in Victoria, the 12th was in Tasmania and the 13th through 15th in Queensland, and so on. This system was overturned in 1912, however, with the introduction of Universal Training (see Conscription). In this scheme unit numbers were allocated to correspond with the new Military Districts that had replaced the old State-based command system. The 1st Military District, based on Queensland, was given the lowest unit numbers and the 2nd Military District, based on New South Wales, was given the next allocation, and again so on. Thus the 1st, 2nd and 3rd Light Horse Regiments, which were in reality existing units renumbered to simply accommodate the new system, were now to be found in Queensland. This change was much to the distaste of some in New South Wales as the military has always associated number allocations with a system of seniority, and making Queensland units the most senior was, in the view of some, a clear usurpation. During this period units were also encouraged to adopt unit subtitles, often based on pre-Federation appellations.
Despite the rationality of this system it was quickly over taken in late 1914 with the raising of the First AIF Territorial factors were still a consideration and throughout the war the authorities would try to recruit and reinforce units from particular states, but with the raising of the 1st Division once again the first unit numbers were allocated to units raised in New South Wales. As the war went on, however, and more units were raised their numbering had more to do with the principle of numerical sequencing than any else, and territorial affiliations and unit numbers had no clear correlation later in the war. The militia units continued with their pre-war system but in 1916, in an effort to transfer some of the spirit of the AIF to the troubled part-time force, it was decided to renumber them to correspond with an AIF unit to which some territorial link, often somewhat tenuous, could be made. The change was made in 1918 and just as the 1st Battalion of the AIF was from New South Wales, so again was the militia 1st Battalion. But because the AIF had followed no clear territorial basis in its system the militia went through the interwar period with a series of numbers that, though based on a recent historical precedent, followed no Military District or state rationale. Partly to ameliorate this, units were again encouraged to adopt subtitles that made regional ties clearer.
With the raising of the Second AIF in 1939 it was decided to introduce yet another scheme. Because the militia divisions had already been numbered 1-6, the new brigade and divisional numbers were continued on in extension from the last war. Thus the first division of the Second AIF was in fact the 6th Division. Battalions were given numbers starting from `1', but to differentiate them from their AIF predecessors and the militia they were each given the number prefix of `2'. Thus the first three battalions of the Second AIF were the 2/1st, 2/2nd and 2/3rd Battalions. When, later in the war, militia units were involved in the Pacific battles it meant there were often units fighting with similar numbers. In New Guinea, for example, there fought both the 25th (originally militia) and the 2/25th Battalions (originally AIF). Supporting units were usually allocated the number of the division of which they were a part. In North Africa the 6th Division included the 6th Divisional Cavalry .Regiment, for example, but there were no similar units carrying the numbers 1 through 5.
After the war and with the establishment of the new Australian Regular Army the new permanent force units of each corps were allocated number serials beginning with `1', but the sequence was followed regardless of the type of units in each corps. This was simple enough for the Royal Australian Infantry in which was raised the 1st, 2nd, 3rd, and eventually up to 9th, Battalions of the Royal Australian Regiment, but was less straightforward elsewhere. Regular armoured units were numbered sequentially but the different roles that each unit had created a variation, so that there is the 1st Armoured Regiment (equipped with tanks); following on from this, however, have been the 2nd, 3rd and 4th Cavalry Regiments (with light armoured vehicles). The same principle means that today the Army has a 16th Air Defence Regiment, but this means only that it is the 16th artillery regiment raised on the order of battle, not that there are another 15 air defence regiments.
Though there was some experimentation in the early postwar period most CMF units, due to their longer historical linkages, had settled back into broadly the same system of numbers and unit subtitles that had been used during the interwar period. With the introduction of the Pentropic battalion organisation in the early 1960s, however, the old militia/AIF battalion numbers and titles were abolished to begin new numbering sequences for each of the newly created state regiments (Royal Queensland Regiment, Royal Tasmanian Regiment etc.). These new regiments were essentially a sop to placate CMF units angry about the changes being forced on them, but with the abandonment of the Pentropic scheme they were kept and grafted to the resurrected old militia/AIF numbers to create units such as the 9th Battalion, Royal Queensland Regiment, or the 3rd Battalion, Royal New South Wales Regiment.
It should be noted that with every one of these systems there have been exceptions, variations and anomalies created by the necessities of administration, such as when raising new units or disbanding old ones. Further variations are created when units are amalgamated and the two unit numbers are kept, in order to preserve traditions or perhaps facilitate a later expansion, such as was done in the 1970s, for example, to create the 2nd/4th, 5th/7th and 8th/9th Battalions of the Royal Australian Regiment.
Citation: The Australian Military, Army Unit Numbering