First Australian Imperial Force History . The 1st AIF was a purely volunteer force for the duration of the war . In Australia , two plebiscites on conscription were defeated , thereby preserving the volunteer status but stretching the AIF ' s reserves towards the end of the war . A total of 331 , 814 Australians were sent overseas to serve as part of the AIF , which represented 13 % of the white male population . Of these , 18 % ( 61 , 859 ) were killed . The casualty rate ( killed or wounded ) was 64 % . About 2 , 100 women served with the 1st AIF , mainly as nurses . Close to 20 % of those who served in the 1st AIF had been born in the United Kingdom but all enlistments had to occur in Australia ( there were a few exceptions ) . As a volunteer force , all units were demobilized at the end of the war . Originally the Australian government pledged to supply 20 , 000 men organised as one infantry division and one light horse brigade plus supporting units . By the end of the war , the 1st AIF comprised 5 infantry divisions and the most part of 2 mounted divisions . The 1st AIF was predominantly a fighting force – the proportion of combat troops to non - combatants ( medical , logistical , etc . ) was exceeded only by the New Zealand Expeditionary Force . When originally formed in 1914 , the AIF was commanded by General William Bridges , who also assumed command of the infantry division . After Bridges ' death at Gallipoli in May 1915 , command transferred by default to General William Birdwood , commander of the Australian and New Zealand Army Corps . Birdwood was officially confirmed as commander of the AIF on 14 September 1916 , while also commanding the I Anzac Corps . After the war finished , all AIF units went into camp and began the process of demobilisation . The exceptions were No . 4 Squadron , Australian Flying Corps and 3rd Australian Casualty Clearing Station , which participated in the occupation of the Rhineland . The 7th Light Horse Regiment was sent to occupy the Gallipoli peninsula , along with a New Zealand regiment . In general , while the British appreciated the fighting qualities of the Australian soldiers , they were not considered docile enough to act as an occupying garrison , and so no Australian infantry were called upon . There were 92 , 000 soldiers in France and a further 60 , 000 in England , 17 , 000 in the Middle East plus nurses in Salonica and India , all to be transported home . By May 1919 , the last troops were out of France , 70 , 000 now encamped on Salisbury Plain . By September , only 10 , 000 remained . General John Monash , the senior Australian commander , was repatriated on 26 December 1919 . The last transport organized to repatriate the troops was the H . T Naldera , which departed London on 13 April 1920 . The 1st AIF officially ceased to exist on 1 April 1921 and on 1 July 1921 the military hospitals in Australia passed into civilian hands . Infantry Divisions . Each division comprised three infantry brigade s and each brigade contained four battalion s . A battalion contained about 1000 men . At the start of the Battle of Gallipoli 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 . After Gallipoli , the infantry underwent a major expansion . The 3rd Division was formed in Australia and sent to France . The original infantry brigades ( 1st to 4th ) were split in half to create 16 new battalions to form another four brigades of infantry . 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 . A 6th Division commenced forming in England in February 1917 but was never deployed to France and was broken up in September of that year . The Australian infantry did not have regiment s in the British sense , only battalions identified by ordinal number ( 1st to 60th ) . Each battalion originated from a geographical region . New South Wales and Victoria , the most populous states , filled their own battalions ( and even whole brigades ) while the " Outer States " often combined to assemble a battalion . These regional associations remained throughout the war and each battalion developed its own strong regimental identity . In 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 , when the call was made to disband eight battalions , there followed 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 AWOL and the doomed battalions were eventually permitted to remain together for the forthcoming battle , following which the survivors voluntarily disbanded . Mounted Divisions . Each division comprised three mounted light horse brigades . The ANZAC Mounted Division so named because it contained one mounted brigade from New Zealand – the New Zealand Mounted Rifles Brigade . Likewise the Australian Mounted Division was originally named the " Imperial Mounted Division " because it contained the British 5th and 6th Mounted Brigade s .