When Serbia failed to comply, Austria-Hungary declared war on July 28, 1914.
Germany, in support of Austria-Hungary, invaded neutral Belgium and Luxembourg and advanced on France, prompting Britain to declare war against the Germans on August 4, 1914.
As part of the British Empire, Australia sent a message to the British government on August 4, 1914, offering "20,000 men of any suggested composition":
Britain sent a reply on August 6, 1914, accepting Australia's offer of 20,000 troops and asking for them to be sent "as soon as possible".
Australia's help was also requested in the urgent seizure of a German wireless station in New Guinea:
The acceptance of Australia's offer of troops saw an outpouring of newspaper coverage on the beginning of the war:
The recruitment drive
After promising an initial force of 20,000 men, Australia needed to recruit the first AIF (Australian Imperial Force).
Propaganda posters were in widespread use in order to recruit troops, with many playing on anti-German sentiment:
Recruitment songs were also widely used. John Bull was a national personification of Great Britain, and in particular England, and was usually depicted as a stout, middle-aged man.
John Bull, a recruitment song
John Bull one day at Westminster was sitting at his ease
And dangling at his side, of course, that famous bunch of keys,
When a rat-tat-tat on the knocker roused him from his reverie,
The first peruse his soul enthused, for this is how it read:
The first one from Australia's side made John look up with pride,
'We have not seen the guns swing round on our Australian shore,
But we'll be there, you need not fear,
When you give us the word.'
Contemporary song, 1914
Some diggers recounted their stories of enlisting when they spoke with historian Harvey Broadbent in 1985.
Troops set sail to join the forces against Germany
Most of the first batches of Australian recruits found themselves bound for the Middle East, and a confrontation with the Ottoman Empire which would reach its climax on the beaches and hills of Gallipoli.