Former coal miner Sapper William Fletcher was part of the 174th Tunnelling Company in the Royal Engineers, digging attack tunnels under enemy lines at the Somme.
But he died aged 41 on October 25 in 1915.
And in April, the Warwickshire man's 1914-15 Star Medal and British War Medal were found by builders at Stechford Industrial Estate.
Police were called and the Warwickshire man's belongings were passed onto the The Royal British Legion, which is appealing for anyone related to the soldier to come forward.
Sapper Fletcher was enlisted in the army on June 10 in 1915, heading out to France four days later with his regiment.
He left behind his wife Mary Sketchley and five children. His last known address was Emery’s Cottage in Ansley, near Nuneaton. His sister, however, was from Lichfield.
The Royal British Legion has researched the soldier and found a handwritten letter from his wife requesting the return of his possessions.
A Census record from 1911 detailing his parents Edward and Ann Fletcher and notification of his death were also found.
A Royal British Legion spokesman said: “We are really keen to reunite William’s medals with his family and we would really like to hear from anyone who can basically fill in the blanks about his story.
"From what we’ve found so far, William was enrolled for his specialist skills being a coal miner and he only served 138 days before being killed at the Somme.
"As like many men he never returned to his family and he left behind a wife and five children. This story is even more poignant as 2018 will mark a century since the end of the First World War and we want to remember those locally who gave their lives.”
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