At just 15 years of age, West Australian stockman Edward Chichele Giles enlisted to fight in the Great War.

Just six months later he died alongside his best mate, James Harrington, on the battlefield in Pozieres, France, aged 16 years and eight days.

Giles is officially the youngest man from WA killed in World War I, and one of 5,209 West Australians who lost their lives as a result of their service on the Western Front.

That figure — which may yet be revised up or down by one — is the result of almost three years of work by 70 volunteers to compile the first comprehensive list of West Australians who served.

Remarkably, in the process, they discovered 158 names which had been left off the State War Memorial.

Historian Shannon Lovelady's team of volunteers found 158 names missing from the State War Memorial. ( ABC News: Manny Tesconi )

Historian Shannon Lovelady, who designed and led the Western Front Dead from Western Australia project, said she spent about 110 hours each week coordinating researchers from across Australia.

Most of the volunteers were family historians with experience in looking at military records.

One volunteer was 92 years old.

"I have volunteers that I haven't even met. You know, some will come to my talks and they'll introduce themselves to me and I'll know them by email, but I won't know their faces," she said.

"I'd give them the surname, the first name and the service number and the unit that [the soldiers] were in and they would go and find them on the National Archives and transcribe the pieces of information that I wanted."

Data from the Commonwealth War Graves Commission website was extracted, supplemented by honour rolls.

The volunteers also transcribed every name on the State War Memorial in Kings Park.

'Breathing life' into stories at risk of disappearing

Ms Lovelady, who also researched the Gallipoli Dead from WA project in 2015, said the Western Front database contained intricate detail of the soldiers.

"The simple stuff was where they enlisted from, where they were born, their occupation, their age on enlistment, next of kin, whether they were married or not and their next of kin's details," she said.

The RSL plans to have the names of 158 soldiers added to the State War Memorial. ( ABC News: Emily Piesse )

Further analysis of the data — which also includes religion and physical appearance — revealed some novel insights.

"The Gallipoli men were predominantly taller and blonder with blue eyes," Ms Lovelady said.

"The Western Front soldiers, as soon as I started seeing the figures coming through, I realised they were shorter and darker."

"In Gallipoli, most were born in Victoria and England, but for the Western Front most were born in Australia and WA."

The team was assisted by two expert panels, including medical professionals, to assess soldiers' eligibility to be on the list.

Ms Lovelady said in some cases, it was difficult to determine whether the soldiers met the list's assessment criteria of having both lived in or enlisted in Western Australia, and died as a result of their service on the Western Front.

"If they were wounded in action in France and then they were invalided to England, and they'd been in England for two months or three months, and then caught the flu and died, were they eligible?" she said.

"That was probably the most tricky [issue] that caused a lot of discussion."

In addition, only soldiers who died on or before August 31, 1921 could be included on the list.

WA is the only state to have a full list of its soldiers who died as a result of serving on the Western Front.

'Commemoration a critical factor'

Over the next 12 months, the Western Front Dead from WA list will be uploaded to the RSLWA database and be accessible to the general public.

The next step will be to add 158 names to the State War Memorial in Kings Park.

RSLWA chief executive John McCourt says commemoration is critical for families, as well as current and former service personnel. ( ABC News: Emily Piesse )

RSLWA chief executive John McCourt estimates that may cost more than $10,000, but says it will be done "come hell or high water".

"It's 158 human beings who have family and who paid the ultimate sacrifice," he said.

"Commemoration is a critical factor, not only for families but for the current serving and ex-service community as well, because it gives them validation."

The RSLWA is preparing an application for funding from the Department of Veterans' Affairs.

"If there's a shortfall, and we have to raise funds through our own efforts, well we'll do that as well," Mr McCourt said.

"It's not only those who are not on the memorial that should be, it's also corrections, misspelling of surnames, wrong initials."

With the Western Front and Gallipoli lists finalised — the latter at 1,024 West Australians — Ms Lovelady said she planned to compile a similar list for the Middle East campaign next year.

She expected that figure is expected to be under 180 names.

The RSL says the names will be added to the war memorial "come hell or high water". ( ABC News: Emily Piesse )

"We will have a definitive number for the number [and names] of Western Australians lost during World War I," she said.

From there, Ms Lovelady said she hoped the database would become a resource for professional researchers and the general public alike.

"I would like people to dive in and find their own family member," Ms Lovelady said.