The British Expeditionary Force (BEF) was tiny and inexperienced in comparison to the French army and so the allies needed to co-ordinate their efforts in order to win against the (also numerous and well-trained) Germans. On the 29th of December, 1915 BEF Commander-in-Chief Douglas Haig was asked to show that Britain was willing to take over more of the frontline and help the French on the Somme.
On 1 July 1916 British troops prepared to mount an attack on German forces along a fourteen mile stretch of the River Somme. Led by Haig, one of the British Army’s main objectives was to reduce the force of the German attack on their French allies fighting at Verdun.
During the battle’s 141 days, casualties on both sides reached over a million. When the campaign finally ended over four months after it had begun, Britain and its allies had seized just seven miles of German territory.