There was also an undertaker, but he was something of an afterthought, according to Richard Reid, manager of the project to bring the soldier home.

When news of the plan to bring the body of an unknown soldier back to Australia got out, the chairman of the Australian Funeral Directors Association got in touch. He offered his expertise and a coffin (soldiers were usually buried in canvas shrouds).

"I think you need a funeral director on the day," the funeral director Rob Allison had said, according to Dr Reid. This struck the organisers in Canberra as very sensible.

The team had identified five graves which might yield what they called "adequate human remains". Australian soldiers - volunteers, remember - were sometimes literally blown to pieces. Shifting soil in other parts of the Somme might have meant graves were actually empty.

By the way, nobody knows why the Adelaide Cemetery was named after the South Australian capital. It would be nice to think it was given the name by villagers grateful to Australian troops who had recaptured Villers-Bretonneux from the Germans on August 8, 1918, but there is no evidence of that.

Either way, the cemetery suited the purpose of those seeking an unidentifiable victim of the "war to end all wars". The remains of soldiers from a range of battles had been brought there so no sleuthing would reveal where the unknown soldier died.

Fortunately, the first grave they tried yielded what they needed. The dismaying prospect of digging up the other four, perhaps with no result at the end, was no more. They would not return empty-handed.

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The unknown soldier in his shroud was raised and put in the coffin. There were no identifying clues to where or how he had died.

Dr Reid said his immediate reaction was one of relief. What might have been a profound emotion was more one of a public servant's relief at a difficult and important task completed.

For him, the emotion welled up later.

The coffin was taken to the Menin Gate, the grand "Memorial to the Missing" at Ypres, Belgium. Six Belgian buglers and an Australian played the Last Post in the frozen night air.

"That, I found very moving. I was emotional that night," Dr Reid said.

The Australian Defence Force provided an honour guard of servicemen and women who had risen at 3am for the task, and who would not have failed to do so under any circumstances.

There was a moment when the coffin was being escorted to an aircraft.

"We were all lined up on the tarmac, and the whole place was shrouded in mist. You couldn't see anything," Dr Reid said.

"All of a sudden, the mist cleared and we could see them marching out of the mist."

There were moments of dark humour.

French conscripts took the coffin from the grave to an ambulance but carried it like luggage - respectfully, but not on their shoulders - until the Australian undertaker intervened to tell them the correct way.

He also hummed the death march to them so they could get the right mournful rhythm to their steps.

And one of the Australian officials picked up some earth from a battlefield to take back for it to be thrown on the coffin in Canberra.

But on entry to Australia, officials from the Customs Service took the sacred earth away and sanitized it, turning it to a fine dust.

The Navy was miffed he was called an "unknown soldier" and not an "unknown warrior" (a term to include sailors). But "warrior" was deemed too grand - and the unknown soldier was ... a soldier.

In the end, the well-laid plans of Australian public servants did come good.

The unknown soldier, exhumed from Plot III, Row M, Grave 13 in the Adelaide cemetery in northern France on November 2, was reburied under the dome of the Australian War Memorial nine days later.

At the reburial, the prime minister captured the moment. Paul Keating said: "He is all of them. And he is one of us."