Battle Of Flers-Courcelette
The Battle of Flers-Courcelette, which began on 15 September 1916 and lasted for one week, was the third and last of the large-scale offensives mounted by the British Army during the Battle of the Somme.
The battle is significant for the first use of the tank in warfare and expectations were high that it would prove a decisive weapon. However, the Mark I tank's performance in the battle was patchy and the British commander-in-chief, General Sir Douglas Haig, has been criticised for revealing the secret weapon too soon. He was warned against this by both his subcommanders (such as E.D. Swinton) and the French government which sent Colonel Jean-Baptiste Eugène Estienne and Subsecretary of State of Inventions Jean-Louis Bréton (normally arch-enemies) to London hoping to persuade the British government to overrule Haig.
Field Marshal Douglas Haig, 1st Earl Haig, KT, GCB, OM, GCVO, KCIE, ADC (19 June 1861 – 29 January 1928) was a British soldier and senior commander (field marshal) during World War I. He commanded the British Expeditionary Force (BEF) from 1915 to the end of the War. Most notably he was commander during the Battle of the Somme, the 3rd Battle of Ypres and the series of victories leading to the German surrender in 1918.
Wikipedia: Battle Of Flers-Courcelette
Wikipedia: World War I