Ninety years ago, at 7.30am on Saturday, 1July 1916, a summer day whose weather, as Siegfried Sassoon wrote, was 'of the kind commonly described as heavenly', whistles blew along the trenches of the Somme Front. Thousands of men, encumbered by sixty pounds of kit, climbed laboriously but obediently over the top and walked into No Man's Land and history. It was the start of 'the Big Push': an offensive that has become a byword for the monstrous stupidity of war. Nearly a century on, as these four books attest, the myth of the greatest battle of the Great War looms as large as ever in the British national consciousness. 

The statistics of the Somme are staggering: on that first day, 60,000 Britons were cut down, 20,000 never to rise again. And that was just the start. By the end of the battle, four and a half months later, more than 450,000 young men of the British Empire had joined