In the long history of the British Army, the Battle of the Somme was its bloodiest encounter. Between July 1 and mid-November 1916, 432 000 of its soldiers became casualties - about 3600 for every day of battle. German casualties were far fewer despite British superiority in the air and in lethal artillery. What went wrong for the British, and who was responsible? This book will decisively change our understanding of the history of the Western Front.