The grave of an unknown New Zealand Army officer buried in Belgium has finally been solved after 103 years.
The grave, number I.E.20 at the Dochy Farm New British Cemetery, has now been confirmed as the final resting place of Captain Ernest Charles Parry of the first Battalion Auckland Infantry Regiment.
He was killed on 6 October, 1917 at the Battle of Passchendaele.
Captain Parry, who was from Paeroa, is commemorated on the New Zealand Tyne Cot Memorial to the missing but until now had no known grave.
He will now finally get a headstone but his name will remain on the Tyne Cot memorial as it is the policy of the Commonwealth War Graves Commission that names not be removed once they have been engraved into the memorial.
Captain Parry's grave was confirmed by a painstaking review of historical material by New Zealand Defence Force historians after an initial case put forward by overseas researchers.
NZDF historian Matthew Buck said the identification was based on two key sources.
"We had some pages added to the war diary of his battalion and a letter from one of his comrades published in the Ohinemuri Gazette in 1917."
He said it was unlikely either would have been found if it was not for the digitalisation programmes carried out recently by Archives New Zealand and the National Library.
The NZDF team found evidence that the bodies of Captain Parry and Sergeant Donald McLean were found lying close together on the battlefield by other members of their battalion.
It said it appeared the bodies were buried together on the battlefield and when they were recovered for reburial at Dochy Farm Cemetery, the graves concentration unit was only able to identify Sergeant McLean and an unknown New Zealand Captain.
Buck said before it could be confirmed as Parry's grave, they had to eliminate it was not the grave of four other New Zealand Infantry captains killed in the same area who had no known resting place.
The Commonwealth War Graves Commission said Captain Parry was the first successful identification case for a New Zealand casualty it was aware of.
There are 6290 New Zealanders who served during World War I who have no known grave.
Captain Parry had two young sons. Both served in the Royal New Zealand Airforce during World War II.
One of them, Flight Sergeant Joseph Parry, was killed on active duty flying with the RAF's 99 squadron on 29 September 1941. He has no known grave.
Buck believes other graves of unknown New Zealand soldiers killed in the First World War may eventually be identified.
He said their descendants often have the missing clues.
"Letters and things like that which were sent from the front to families from comrades of men who had been killed which often in fact end up holding the vital clues, and as they emerge over the years. There's reasonable optimism that this won't be a unique case."
Buck said confirmation of the grave came after five years of painstaking research by many people.
"If we get it wrong then another family is going to lose out and on top of that we are also aware from doing this work that the impact of these tragedies on families was very great indeed and could have cascading effects in fact, so these are all the things we bear in mind when we are looking at cases like this."