The extension to the Mesnil-Martinsart Communal Cemetery was built in July 1916, at the time of the Battle of the Somme, and contains 333 graves: 321 British, 5 Canadians, and 7 New Zealanders.
Since the village of Mesnil was located near the front until September 1916, and again from March to August 1918, this cemetery was begun in July, at the time of the Battle of the Somme. Although bodies were still being buried in 1918, it was mainly after the armistice that a large number of bodies from the nearby battlefield, located northeast of Mesnil, were gathered here. This was the case for 141 British sailors and soldiers, as well as the Canadians from Mesnil Dressing Station Cemetery. This cemetery was located during the war to the west of the village, near a small railway line, which was mainly used to transport munitions. It was used from June 1916 to February 1917, and again from March to July 1918, mainly by the 63rd Division: the Royal Naval Division