[1] Dunville was educated at Ludgrove School and Eton College, and was a member of the Officers' Training Corps from May 1912 to July 1914.
[2] He was aged 21 and a second lieutenant in the 1st (Royal) Dragoons, British Army during the First World War when he was awarded the Victoria Cross for his actions on 25 June 1917 near Épehy, France.
When in charge of a party consisting of scouts and Royal Engineers engaged in the demolition of the enemy's wire, this officer displayed great gallantry and disregard of all personal danger.
2nd Lt. Dunville, although severely wounded, continued to direct his men in the wire-cutting and general operations until the raid was successfully completed, thereby setting a magnificent example of courage, determination and devotion to duty, to all ranks under his command.
This gallant officer has since succumbed to his wounds.Second Lieutenant John Spencer Dunville died of wounds on 26 June 1917, the day after performing the deed, and is interred at the Villiers-Faucon Communal Cemetery, Somme, France, (Plot No.