Redgum's iconic I Was Only 19 has been re-recorded by the band's John Schumann with Australian band The Waifs to commemorate its 40th anniversary.
Royalties from the new version will go towards the Commando Welfare Trust which provides support where the existing veterans' services don't.
According to the Australian War Memorial, the original version was released in March 1983 when Vietnam War - which divided public opinion a decade earlier - was avoided in polite conversation.
"A generation of veterans had been left feeling isolated and with a belief they had been forgotten by their country. I was only 19 provided a fresh perspective, presenting a compelling sympathetic account of an Australian soldier's experience of the war and its aftermath," the memorial said.
"Concentrating on the toll paid by those who took part rather than debating the merits of the war itself, it became the quintessential song of the Australian Vietnam War veteran."

Schumann used the experiences of his brother-in-law Mick Storen, who served with 3 Platoon, A Company, 6 Battalion, Royal Australian Regiment (6RAR) in Vietnam in 1969, in the lyrics.
Its impact on people in Australia has been profound: the song has become part of Anzac Day services, features in Australian War Memorial exhibitions, is taught in schools and there's a children's book.
Forty years later, the song still carries humanity, connecting us as a society. It speaks truth to power.
Back then, it called on the fairness and decency which is innate in Australians. Now, it calls on us to always respect and support the men and women our government send off to war, regardless of what our consciences might say about our involvement in a particular conflict.
Recording a 40th anniversary version
In his essay reflecting on the 40th anniversary of I was only 19, Schumann's friend, poet and journalist, Warwick McFadyen, wrote "our soldiers do not die in conflict upon our shores. They are not wounded on our streets. The thread of war is spun in foreign lands, where it stretches tight, snaps, and loosens. And when the soldiers return, the thread stays with them.
"Sometimes it is invisible, sometimes all too visible. When the veterans of the Vietnam war came home, they were not greeted with cheers, rather a great silence which seeped into their bones. It turned duty into a shroud."
The 40th anniversary video can be watched below.
Australian band The Waifs joined Schumann for the re-record, which was produced by acclaimed singer-songwriter and record producer, Shane Nicholson.
'19' carried Schumann down a path into the world of vets grappling and suffering with post-traumatic stress disorder. He has been a staunch advocate for their welfare.
When recording and production costs are recouped, the Waifs and Schumann have directed the artist royalties to the Commando Welfare Trust which provides support where the existing veterans' services don't.
Schumann said: "It's worth recalling that of the 41 Australians who were killed in Afghanistan, 16 were Commandos. At this time, when there's a bit of negative media coverage around - particularly about Australian Special Forces - we understand that right now many veterans are feeling diminished.
"This small gesture is us wanting to stand beside them and remind Australians that the vast majority of Afghanistan veterans served bravely and honourably."
The song can be streamed and bought digitally here.
Need to talk?
- Open Arms: 1800 011 046, www.openarms.gov.au
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