BBC "One Show" website has lots of background information.
"The photographs were taken by a French couple, Louis and Antoinette Thuillier during the First World War and are a fantastic and very natural collection of portraits of Allied soldiers who were billeted in the village when they were away from the trenches."
"What makes the pictures all the more powerful is that the village of Vignacourt was a days march from the frontline that would be the centre of the Battle of the Somme, so a lot of the men who had their photos taken would have died weeks or even days later. "
The Lost Tommies
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