Editing First Australian Imperial Force (section)

====Infantry divisions====
{{See also|List of Australian divisions in World War I}}
[[Image:Australian 11th Battalion group photo.jpg|thumb|right|alt=Black and white photo of a large number of men wearing military uniform seated on stone steps|Soldiers from the [[11th Battalion (Australia)|11th Battalion]] posing on the [[Great Pyramid of Giza]], 1915.]]
The organisation of the AIF closely followed the British Army divisional structure, and remained relatively unchanged throughout the war. During the war, the following infantry divisions were raised as part of the AIF:{{sfn|Palazzo|2001|pp=67–68}}
* 1st Division
* 2nd Division
* [[3rd Division (Australia)|3rd Division]]
* [[4th Division (Australia)|4th Division]]
* [[5th Division (Australia)|5th Division]]
* [[6th Division (Australia)|6th Division]] (broken up in 1917 before seeing combat){{sfn|Palazzo|2001|p=67}}
* [[New Zealand and Australian Division]] (1915){{sfn|Grey|2001|p=40}}

Each division comprised three infantry brigades, and each brigade contained four battalions (later reduced to three in 1918).{{sfn|Grey|2001|p=67}} Australian battalions initially included eight rifle [[company (military)|companies]]; however, this was reduced to four expanded companies in January 1915 to conform with the organisation of British infantry battalions. A battalion contained about 1,000 men.{{sfn|Kuring|2004|p=47}} Although the divisional structure evolved over the course of the war, each formation also included a range of combat support and service units, including [[List of Australian Army Artillery units in World War I|artillery]], [[Australian Machine Gun Corps|machine-gun]], [[mortar (weapon)|mortar]], engineer, [[Pioneer (military)|pioneer]], [[Military communications|signals]], [[Military logistics|logistic]], [[List of Australian Army medical units in World War I|medical]], [[Australian Army Veterinary Corps|veterinary]] and [[Military administration|administrative]] units. By 1918 each brigade also included a light trench mortar battery, while each division included a pioneer battalion, a machine-gun battalion, two field artillery brigades, a divisional trench mortar brigade, four companies of engineers, a divisional signals company, a divisional [[Train (military)|train]] consisting of four [[Royal Australian Army Service Corps|service corps]] companies, a salvage company, three [[field ambulance]]s, a sanitary section and a mobile veterinary section.{{sfn|Stevenson|2013|p=55}} These changes were reflective of wider organisational adaption, tactical innovation, and the adoption of new weapons and technology that occurred throughout the [[British Expeditionary Force (World War I)|British Expeditionary Force]] (BEF).{{sfn|Stevenson|2013|pp=56–57}}

At the start of the Gallipoli Campaign, the AIF had four infantry brigades with the first three making up the 1st Division. The 4th Brigade was joined with the sole New Zealand infantry brigade to form the New Zealand and Australian Division. The 2nd Division had been formed in Egypt in 1915 and was sent to Gallipoli in August to reinforce the 1st Division, doing so without its artillery and having only partially completed its training. After Gallipoli, the infantry underwent a major expansion. The 3rd Division was formed in Australia and completed its training in the UK before moving to France. The New Zealand and Australian Division was broken up with the New Zealand elements forming the [[New Zealand Division]], while the original Australian infantry brigades (1st to 4th) were split in half to create 16 new battalions to form another four brigades. These new brigades (12th to 15th) were used to form the 4th and 5th Divisions. This ensured the battalions of the two new divisions had a core of experienced soldiers.{{sfn|Grey|2008|pp=99–100}}{{sfn|Bean|1941c|pp=36–42}} The 6th Division commenced forming in England in February 1917, but was never deployed to France and was broken up in September of that year to provide reinforcements to the other five divisions.{{sfn|Dennis et al|2008|p=187}}

The Australian infantry did not have regiments in the [[Regiment#British Army|British sense]], only battalions identified by [[ordinal number]] (1st to 60th). Each battalion originated from a geographical region, with men recruited from that area. [[New South Wales]] and [[Victoria, Australia|Victoria]], the most populous states, filled their own battalions (and even whole brigades) while the "Outer States"—[[Queensland]], [[South Australia]], [[Western Australia]] and [[Tasmania]]—often combined to assemble a battalion. These regional associations remained throughout the war and each battalion developed its own strong regimental identity.{{sfn|Dennis et al|2008|p=63}} The pioneer battalions (1st to 5th, formed from March 1916) were also mostly recruited regionally; however, the machine-gun battalions (1st to 5th, formed from March 1918 from the brigade and divisional machine-gun companies) were made up of personnel from all states.{{sfn|Kuring|2004|pp=83–84 & 90–92}}{{refn|The machine-gun companies usually had a state affiliation; however, this was not maintained later in the war when they were formed into battalions.<ref>{{cite web|last=Mallett|first=Ross|url=http://www.aif.adfa.edu.au:8888/main.html|archive-url=https://web.archive.org/web/20150228202933/http://www.aif.adfa.edu.au:8888/|title=Part B: Branches&nbsp;– Machine Gun Corps|work=First AIF Order of Battle 1914–1918|publisher=Australian Defence Force Academy|access-date=5 January 2015|archive-date=28 February 2015}}</ref> |group=Note}}

During the manpower crisis following the [[Third Battle of Ypres]], in which the five divisions sustained 38,000 casualties, there were plans to follow the British reorganisation and reduce all brigades from four battalions to three. In the British [[regimental system]] this was traumatic enough; however, the regimental identity survived the disbanding of a single battalion. In the Australian system, disbanding a battalion meant the extinction of the unit. In September 1918, the decision to disband seven battalions—the [[19th Battalion (Australia)|19th]], [[21st Battalion (Australia)|21st]], [[25th Battalion (Australia)|25th]], [[37th Battalion (Australia)|37th]], [[42nd Battalion (Australia)|42nd]], [[54th Battalion (Australia)|54th]] and [[60th Battalion (Australia)|60th]]—led to a series of "mutinies over disbandment" where the ranks refused to report to their new battalions. In the AIF, [[mutiny]] was one of two charges that carried the death penalty, the other being desertion to the enemy. Instead of being charged with mutiny, the instigators were charged as being [[absent without leave]] (AWOL) and the doomed battalions were eventually permitted to remain together for the forthcoming battle, following which the survivors voluntarily disbanded.<ref>{{cite encyclopedia |url=https://www.awm.gov.au/encyclopedia/first_aif/mutinies/ |title=Mutinies in the 1st Australian Imperial Force (AIF) |encyclopedia=Encyclopedia |publisher=Australian War Memorial |access-date=13 December 2014}}</ref> These mutinies were motivated mainly by the soldiers' loyalty to their battalions.{{sfn|Stanley|2010|p=211}}

The artillery underwent a significant expansion during the war. When the 1st Division embarked in November 1914 it did so with its [[Ordnance QF 18 pounder|18-pounder]] field guns, but Australia had not been able to provide the division with the howitzer batteries or the heavy guns that would otherwise have been included on its establishment, due to a lack of equipment. These shortages were unable to be rectified prior to the landing at Gallipoli where the howitzers would have provided the [[plunging fire|plunging]] and high-angled fire that was required due to the rough terrain at [[Anzac Cove]].{{sfn|Palazzo|2001|pp=66–67}}{{sfn|Stevenson|2013|p=43}} When the 2nd Division was formed in July 1915 it did so without its complement of artillery. Meanwhile, in December 1915 when the government offered to form another division it did so on the basis that its artillery would be provided by Britain.{{sfn|Palazzo|2001|pp=66–67}} In time though these shortfalls were overcome, with the Australian field artillery expanding from just three field brigades in 1914 to twenty at the end of 1917. The majority of the heavy artillery units supporting the Australian divisions were British, although two Australian heavy batteries were raised from the regular Australian Garrison Artillery. These were the 54th Siege Battery, which was equipped with [[BL 8-inch howitzer Mk I–V|8-inch howitzers]], and the 55th with [[BL 9.2-inch howitzer|9.2-inch howitzer]]s.{{sfn|Horner|1995|pp=80–81}}