The Battle of Fromelles (; 19–20 July 1916), was a British military operation on the Western Front during World War I, subsidiary to the Battle of the Somme. General Headquarters (GHQ) of the British Expeditionary Force (BEF) had ordered the First Army and Second Army to prepare attacks to support the Fourth Army on the Somme to the south, to exploit any weakening of the German defences opposite. The attack took place from Lille between the Fauquissart–Trivelet road and Cordonnerie Farm, an area overlooked from Aubers Ridge to the south. The ground was low-lying and much of the defensive fortification on both sides consisted of breastworks, rather than trenches.