The First World War began in August of 1914

At first Joffre intended for to use mainly French soldiers but the German attack on  in February 1916 turned the Somme offensive into a large-scale British diversionary attack. General  now took over responsibility for the operation and with the help of General Sir , came up with his own plan of attack. Haig's strategy was for a eight-day  that he believed would completely destroy the German forward defences.

General  was was in charge of the main attack and his Fourth Army were expected to advance towards Bapaume. To the north of Rawlinson, General  and the British Third Army were ordered to make a breakthrough with cavalry standing by to exploit the gap that was expected to appear in the German front-line. Further south, General Fayolle was to advance with the French Sixth Army towards Combles. 

Haig used 750,000 men (27 divisions) against the German front-line (16 divisions). However, the bombardment failed to destroy either the barbed-wire or the concrete bunkers protecting the German soldiers. This meant that the Germans were able to exploit their good defensive positions on higher ground when the British and French troops attacked at 7.30 on the morning of the 1st July. The BEF suffered 58,000 casualties (a third of them killed), therefore making it the worse day in the history of the British Army. 

Haig was not disheartened by these heavy losses on the first day and ordered General  to continue making attacks on the German front-line. A night attack on 13th July did achieve a temporary breakthrough but German reinforcements arrived in time to close the gap. Haig believed that the Germans were close to the point of exhaustion and continued to order further attacks expected each one to achieve the necessary breakthrough. Although small victories were achieved, for example, the capture of Pozieres on 23rd July, these gains could not be successfully followed up.