The origin is complex and can well be attributed to that famous photographer Damien Parer.
Almost every war has a battle which captures the imagination of the public. During the Second World War a number of Australia's victories received wide acclaim but it was Parer's Kokoda Trail film, depicting the terrain, the horrific conditions confronting our young soldiers and the suffering of the wounded, that made the greatest impact. Its images were adopted by the public as representing all the fighting in the islands.
After the war various army formations and units, the navy, the air force and the merchant navy proceeded to commemorate those engagements which were the most meaningful to them, and Kokoda Day was born.
In addition to the public's image of the Kokoda Trail campaign, many peoples believed the outcome of that campaign was what saved Australia from invasion. Consequently, of all the commemorative services Kokoda Day received the most publicity. However there were other famous battles fought, and naturally those who fought in them felt themselves unfairly treated.
As time passed a spate of histories written about the Second World War better informed Australians, and it was recalled that our wartime Prime Minister had used the description 'Battle for Australia' similarly to Britain's Prime Minister Churchill's naming of the 'Battle for Britain'. Then in 1995, the 'Australia Remembers' initiative of the Department for Veterans' Affairs greatly added to knowledge of Australia's critical years.
The RAAF Association in Victoria was the first organisation to seek to take advantage of this new public interest. It felt that such interest needed to be expanded, particularly among the young, and that those who had fought and repelled the Japanese warranted better recognition, A submission was made to the Victorian RSL and on-forwarded to the RSL's National Executive which, in December 1997, resolved that there should be a Battle for Australia Day of commemoration. The movement gained momentum, a Battle for Australia Council was formed, and a commemorative ceremony was held at the Melbourne Shrine of Remembrance on 5 September 1998.
In New South Wales Kokoda Day, following on its 50th anniversary celebration on 2 November 1992, continued to grow. In 1995 the Kokoda Day Committee became incorporated and, dropping the 'Day', called the commemoration 'Kokoda Commemoration'. However pressure was mounting on the committee to widen its scope, and on 23 February 1999 it advised the Battle for Australia Council that it would relinquish its title and become the council's NSW Branch.
Below is another of Damien Parer's efforts. This time about the defence of Port Moresby.