World War One: Artist Christopher Williams's Mametz
A World War One work by artist Christopher Williams, showing the battle of Mametz Wood in the Somme, is the centrepiece of a new centenary exhibition at National Museum Wales in Cardiff.
About 4,000 men from the 38th (Welsh) Division were killed or injured at Mametz Wood during the battle of the Somme.
Williams, a pacifist, was commissioned to travel to the western front a few months after the battle in July 1916.
Prof Robert Meyrick of Aberystwyth University, an expert on Williams's work, told BBC Wales arts and media correspondent Huw Thomas about how the painting came about.
The exhibition War's Hell!: The Battle of Mametz Wood in Art , externalwill be at National Museum Cardiff until 4 September 2016.