ROBERT MENZIES: (ON RADIO) Fellow Australians,
it is my melancholy duty to inform you officially
that in consequence of a persistence by Germany
in her invasion of Poland,
Great Britain has declared war upon her,
and that, as a result, Australia is also at war.
JACK: This was the announcement broadcast across the country
that marked the start of Australia's role
in the Second World War.
Back then, Australia was still part of the British Empire
and strongly believed in supporting Britain,
but the country wasn't really prepared for another war.
The army only had around 3,000 soldiers,
so the military set out to recruit a new expeditionary force
to fight across land, sea and sky.
There was also the Citizens Military Forces, or Militia,
which was similar to today's Army Reserve.
In 1942, the government made it compulsory
for all men aged between 18 and 35 to join the CMF.
Some would end up on the front lines.
By the end of the Second World War,
close to a million Aussies would serve.
That included more than 5,000 Indigenous soldiers,
who signed up to fight for a country
that didn't yet count them as citizens.
Women also played a much bigger role in the Second World War.
For the first time, they were allowed to enlist in the armed forces.
And by the end of the war,
they were serving in all sorts of roles,
from driving to manning anti-aircraft guns.
Women also kept the economy going at home,
taking on many of the jobs usually done by men.
At first, many Australian soldiers were sent to fight in Europe,
the Mediterranean and North Africa,
but in 1941, the war got a lot closer to home.
Japan, which was already at war with China,
attacked British, Dutch and American territories
in Asia and the Pacific.
It had allied itself with Nazi Germany
and had its own plans to control the whole Pacific region.
Its army swept across South-East Asia,
and many feared Australia would be next.
After brief attacks on the city of Darwin
and submarine attacks in Sydney and Newcastle,
they began an invasion
of New Guinea,
which was an Australian territory
at the time.
The Japanese navy wanted
to take control of the capital, Port Moresby, by sea,
but they were defeated by US and Australian forces
in a major naval and aerial battle known as the Battle of the Coral Sea.
Meanwhile, a force of 2,000 Japanese soldiers set out
to take Port Moresby overland,
trekking across a track we now know as Kokoda.
They were met by a much smaller group of Australian soldiers
who were trekking towards an airfield in the north,
and the Battle of Kokoda began.
It's remembered as one of the most difficult campaigns of the war.
The soldiers, who were mostly young and inexperienced,
battled not just the Japanese but also the elements.
The Kokoda Track is tough. It's narrow, steep and muddy.
The days were hot and the nights freezing.
By the time they even encountered the Japanese,
they would be exhausted.
However, they persisted,
and with help from local Papuan people
and additional soldiers that were sent in,
they were able to stop Japan from taking control.
For the next three years,
Australians continued to fight in the Pacific
and in Europe and the Middle East
until the tide of war turned against the Nazis,
and then against Japan.
By the end of the war, close to 30,000 Australians had died.
Many more were injured physically and mentally,
including the tens of thousands who spent time as prisoners of war.
They and the country they left behind
would be forever changed by the Second World War.