This was the largest British offensive mounted in 1915 on the Western Front. The British would have preferred to remain on the defensive until the BEF numbered 36 divisions and had built up sufficient stocks of ammunition and heavy artillery. However this meant waiting until Spring 1916 and, with the Russians under severe pressure on the Eastern front and the Gallipoli campaign faltering, this was politically impossible.
Sir John French's anxiety over the lack of suitable munitions unwisely led him to involve the military reporter Charles Repington. This action ignited a huge controversy back in Britain. The British Army was committed to a battle not of its choosing, in an area unsuited to an attack, without clear objectives and with its major commanders (French and Haig) at loggerheads.
The opening saw the first use of poison gas by the British Army, following its introduction by the Germans, and was the first mass engagement of New Army units. Despite heavy casualties, there was considerable success on the first day but the reserve divisions were held too far from the battle front and the whole attack became bogged down.
Sir John French had already been much criticised before the battle and his perceived poor handling of his reserve divisions in the battle led to his remaining support in both the Government and Army being severely eroded.He was replaced by Douglas Haig as Commander of the British Expeditionary Force in December 1915.
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Long, Long Trail