Editing First Australian Imperial Force (section)

===Structure===
{{main|Structure of the Australian Army during World War I}}

====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}}

====Mounted divisions====
[[Image:Light horse walers.jpg|thumb|right|alt=Black and white photo of a man wearing military uniform with a rifle slung across his back riding a horse. Two other similarly dressed men are partly visible in the background.|Australian light horsemen]]
The following mounted divisions were raised as part of the AIF:{{sfn|Palazzo|2001|p=68}}
* [[ANZAC Mounted Division]]
* [[Australian Mounted Division]]

During the Gallipoli Campaign four light horse brigades had been dismounted and fought alongside the infantry divisions.{{sfn|Kuring|2004|p=84}} However, in March 1916 the ANZAC Mounted Division was formed in Egypt (so named because it contained one mounted brigade from New Zealand – the [[New Zealand Mounted Rifles Brigade]]). Likewise, the Australian Mounted Division—formed in February 1917—was originally named the Imperial Mounted Division because it contained the British [[5th Mounted Brigade|5th]] and [[6th Mounted Brigade]]s.{{sfn|Fleming|2012|pp=7–8}} Each division consisted of three mounted light horse brigades.{{sfn|Bou|2010a|pp=27–29}} A light horse brigade consisted of three regiments. Each regiment included three [[squadron (army)|squadrons]] of four [[troops]] and a machine-gun section. The initial strength of a regiment was around 500 men, although its establishment changed throughout the war.{{sfn|Bou|2010b|pp=141–142}} In 1916, the machine-gun sections of each regiment were concentrated as squadrons at brigade-level.{{sfn|Bou|2010b|p=166}} Like the infantry, the light horse regiments were raised on a territorial basis by state and were identified numerically (1st to 15th).{{sfn|Bou|2010b|p=142}}

====Corps====
The following corps-level formations were raised:{{sfn|Fleming|2012|pp=5–7}}
* Australian and New Zealand Army Corps
* I ANZAC Corps
* II ANZAC Corps
* Australian Corps
* Desert Mounted Corps (formerly the [[Desert Column]])
The Australian and New Zealand Army Corps (ANZAC) was formed from the AIF and NZEF in preparation for the Gallipoli Campaign in 1915 and was commanded by Birdwood. Initially the corps consisted of the 1st Australian Division, the New Zealand and Australian Division, and two mounted brigades—the Australian 1st Light Horse Brigade and the New Zealand Mounted Rifles Brigade—although when first deployed to Gallipoli in April, it did so without its mounted formations, as the terrain was considered unsuitable. However, in May, both brigades were dismounted and deployed along with the 2nd and 3rd Light Horse Brigades as reinforcements. Later, as the campaign continued the corps was reinforced further by the 2nd Australian Division, which began arriving from August 1915. In February 1916, it was reorganised into I and II ANZAC Corps in Egypt following the evacuation from Gallipoli and the subsequent expansion of the AIF.{{sfn|Fleming|2012|pp=5–6}}

I ANZAC Corps included the Australian 1st and 2nd Divisions and the New Zealand Division. The New Zealand Division was later transferred to the II ANZAC Corps in July 1916 and was replaced by the Australian 3rd Division in I ANZAC. Initially employed in Egypt as part of the defence of the [[Suez Canal]], it was transferred to the Western Front in March 1916. II ANZAC Corps included the Australian 4th and 5th Divisions, forming in Egypt it transferred to France in July 1916.{{sfn|Fleming|2012|p=6}} In November 1917 the five Australian divisions of I and II ANZAC Corps merged to become the Australian Corps, while the British and New Zealand elements in each corps became the [[XXII Corps (United Kingdom)|British XXII Corps]]. The Australian Corps was the largest corps fielded by the British Empire in France, providing just over 10 percent of the manning of the BEF.{{sfn|Kuring|2004|p=70}} At its peak it numbered 109,881 men.{{sfn|Fleming|2012|p=7}} Corps troops raised included the [[13th Light Horse Regiment (Australia)|13th Light Horse Regiment]] and three army artillery brigades.{{sfn|Palazzo|2001|p=68}} Each corps also included a [[Australian Cycling Corps|cyclist battalion]].{{sfn|Fitzpatrick|1983|pp=31–38}}

Meanwhile, the majority of the Australian Light Horse had remained in the Middle East and subsequently served in Egypt, Sinai, Palestine and Syria with the Desert Column of the Egyptian Expeditionary Force. In August 1917 the column was expanded to become the Desert Mounted Corps, which consisted of the ANZAC Mounted Division, Australian Mounted Division and the [[Imperial Camel Corps Brigade]] (which included a number of Australian, British and New Zealand camel companies).{{sfn|Fleming|2012|pp=7–8}} In contrast to the static [[trench warfare]] that developed in Europe, the troops in the Middle East mostly experienced a more fluid form of warfare involving manoeuvre and combined arms tactics.{{sfn|Blaxland|2006|p=24}}

====Australian Flying Corps====
[[File:No 1 Squadron AFC Mejdel 1918.jpg|thumb|alt=Black and white photograph of a large group of men dressed in military uniform standing in close formation next to a row of biplane aircraft|Members of No. 1 Squadron and their fighter aircraft in February 1918]]

The 1st AIF included the [[Australian Flying Corps]] (AFC). Soon after the outbreak of war in 1914, two aircraft were sent to assist in capturing German colonies in what is now north-east New Guinea. However, these colonies surrendered quickly, before the planes were even unpacked. The first operational flights did not occur until 27 May 1915, when the [[Mesopotamian Half Flight]] was called upon to assist the [[British Indian Army|Indian Army]] in protecting British oil interests in what is now [[Iraq]].{{sfn|Dennis et al|2008|pp=61–62}} The corps later saw action in [[Egypt]], [[Palestine (region)|Palestine]] and on the Western Front throughout the remainder of World War I. By the end of the war, four squadrons—[[No. 1 Squadron RAAF|Nos. 1]], [[No. 2 Squadron RAAF|2]], [[No. 3 Squadron RAAF|3]] and [[No. 4 Squadron RAAF|4]]—had seen operational service, while another four training squadrons—[[No. 5 Squadron RAAF|Nos. 5]], [[No. 6 Squadron RAAF|6]], [[No. 7 Squadron RAAF|7]] and [[No. 8 Squadron RAAF|8]]—had also been established. A total of 460 officers and 2,234 other ranks served in the AFC.{{sfn|Grey|1999|pp=114–115}} The AFC remained part of the Australian Army until 1919, when it was disbanded; later forming the basis of the [[Royal Australian Air Force]].<ref>{{cite web| url=http://www.airforce.gov.au/raafmuseum/| title=RAAF Museum Point Cook| publisher=Royal Australian Air Force| access-date=7 June 2012}}</ref>

====Specialist units====
A number of specialist units were also raised,{{sfn|Palazzo|2001|p=67}} including three Australian [[Tunnelling companies of the Royal Engineers|tunnelling companies]]. Arriving on the Western Front in May 1916 they undertook [[Mining (military)|mining and counter-mining]] operations alongside British, Canadian and New Zealand companies, initially operating around [[Armentieres]] and at [[Fromelles]]. The following year they operated in the [[Ypres]] section. In November 1916, the [[1st Australian Tunnelling Company]] took over from the Canadians around [[Battle of Hill 60 (Western Front)|Hill 60]], subsequently playing a key role in the [[Battle of Messines (1917)|Battle of Messines]] in June 1917. During the German offensive in March 1918 the three companies served as infantry, and later supported the Allied advance being used to defuse booby traps and mines.{{sfn|Dennis et al|2008|pp=368–369}} The Australian Electrical Mining and Mechanical Boring Company supplied electric power to units in the [[British Second Army]] area.{{sfn|McNicoll|1979|pp=180–183}}

Motor transport units were also formed. Not required at Gallipoli, they were sent on to the Western Front, becoming the first units of the AIF to serve there. The motor transport rejoined I ANZAC Corps when it reached the Western Front in 1916.{{sfn|Bean|1941c|p=115}} Australia also formed six railway operating companies, which served on the Western Front.{{sfn|McNicoll|1979|p=173}} Specialist ordnance units included ammunition and mobile workshops units formed late in the war, while service units included supply columns, ammunition sub-parks, field bakeries and butcheries, and depot units.<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;– Ordnance|work=First AIF Order of Battle 1914–1918|publisher=Australian Defence Force Academy|access-date=27 December 2014|archive-date=28 February 2015}}</ref><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;– Service|work=First AIF Order of Battle 1914–1918|publisher=Australian Defence Force Academy|access-date=27 December 2014|archive-date=28 February 2015}}</ref> Hospitals and other specialist medical and dental units were also formed in Australia and overseas, as were a number of convalescent depots.<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;– Medical|work=First AIF Order of Battle 1914–1918|publisher=Australian Defence Force Academy|access-date=27 December 2014|archive-date=28 February 2015}}</ref>
One small armoured unit was raised, the 1st Armoured Car Section. Formed in Australia, it fought in the Western Desert, and then, re-equipped with [[Ford Model T|T Model Ford]]s, served in Palestine as the [[1st Light Car Patrol (Australia)|1st Light Car Patrol]].{{sfn|Bean|1941c|pp=965–967}}{{refn|In March 1918, the British War Office had offered to provide all necessary equipment to the Australians to form their own tank battalion; however, this was turned down by Birdwood due to a lack of manpower.{{sfn|Blaxland|2006|p=35}}{{sfn|Grey|2001|p=94}}|group=Note}} Camel companies were raised in Egypt to patrol the Western Desert. They formed part of the [[Imperial Camel Corps]] and fought in the Sinai and Palestine.{{sfn|Gullett|1941|pp=210–212}} In 1918 they were converted to light horse as the [[14th Light Horse Regiment (Australia)|14th]] and [[15th Light Horse Regiment (Australia)|15th Light Horse Regiment]]s.{{sfn|Gullett|1941|p=640}}