They were posted by William Stocker to Daisy Palmer between 1914-18 and were stumbled upon by his family going through possessions after his death in 1989.
Around 300 letters were found, but it is only in the past couple of years that granddaughter Karen Stocker has been able to compile them in the book My Dear Daisy... Letters to Fulham from the Front.
The couple were both born and grew up in Fulham and their family believe they met at Twynholm Baptist Church, or Church of Christ as it was then.
When war broke out he was living in Waldemar Avenue, while Miss Palmer resided in Crabtree Lane.
Topics in the letters range from the horrors he witnesses in the field of conflict to more trivial matters such as blunt razors.
The letters deal with the difficulties of being separated and how William was buoyed by his faith and hopes for the future.
For Karen, compiling the letters often proved difficult.
She said: “It was very emotional.
“It’s as if my grandfather was two people. The grandfather that I knew, and the man that wrote these letters that I didn’t know."
“He didn’t really talk about the war much. He’d seen so many ghastly things and either he didn’t want to remember it or he wanted to protect us," said Karen.
Mr Stocker was born in 1892 and during the Great War served in the Royal Army Medical Corp during battles including those in Ypres and the Somme.
His unit set sail for France on March 14 1915 and during his second leave, in 1917, he married his beloved.
His war was cut short in March 1918, when leaving his dugout on the first day of the German Spring Offensive with other stretcher bearers he was badly hurt by an exploding shell. Two men near him died and but Mr Stocker survived despite losing part of his foot.
Karen says: “When I think back he did walk with a limp but I never knew why. It was just the way my grandfather walked.
“I was very little and didn’t think anything of it. It was not until someone told me that he was hurt during the First World War that I found out.
“But he rarely spoke to anyone about the war. I think he just didn’t want to be reminded of it.”
Following the war, Mr Stocker returned to Fulham, before moving in the 1920s across the river to Putney.
Over the coming decades he worked as a teacher in west London schools, including the now closed Sherbrooke School in Fulham.
The book includes illustrations, original poems, family recollections and a tape recording made by Mr Stocker shortly before his death.
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