Australian and New Zealand Army

In early 1916 the Australian and New Zealand governments proposed that an Australian and New Zealand Army be established to control the units of the First Australian Imperial Force (AIF) and New Zealand Expeditionary Force (NZEF). The British Government rejected this proposal on the grounds that the forces were insufficient to justify a separate field army, and the Australian and New Zealand units served as part of British armies for the remainder of World War I. The Australian units were grouped into the Australian Corps in late 1917.

Following the withdrawal of the Australian and New Zealand Army Corps from Gallipoli to Egypt in December 1915, Lieutenant-General William Birdwood, the commander of the AIF, was appointed to the temporary position of commander of the Australian and New Zealand Forces. In his role he was to oversee the reorganisation of the Australian combat divisions and the formation of the New Zealand Division. At this time the Australian and New Zealand Governments hoped to establish an Australian and New Zealand Army comprising two corps under the command of Birdwood. Birdwood was an ambitious officer, and agitated for such a command.

In early 1916 Australian Government telegraphed the British Government supporting Birdwood's proposal to establish an Australian and New Zealand Army. The Australian Government argued that the establishment of this force would reflect Australian aspirations and encourage enlistment in the AIF. It is not clear whether the New Zealand Government supported the proposal at this time. On 2 April 1916 the British War Office responded, declining to establish such a formation but claiming that it would do so "as soon as circumstances permit". The next month the Australian Government offered to establish a sixth division; such an offer aimed to provide enough divisions to justify the formation of an army. However, this proposal was also rejected by the British as it was unclear whether Australia would be able to provide sufficient reinforcements to replace the AIF's casualties if the division was formed. During this period Birdwood also encouraged the formation of a Dominion Army which would have included the Canadian forces in France as well as the AIF and NZEF; Birdwood also hoped to command this army.

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