The Somme offensive began with the Battle of Albert in high summer and petered out with the Battle the Ancre, fought in winter mud. Its huge casualty rate is well known, and also its strategic futility - territorial gains for the British and French were never commensurate to their manpower losses. The battle, or rather series of battles, is very well documented and many writers took part - Edmund Blunden, Gerald Brenan, Robert Graves, Tom Kettle, Ford Madox Ford (then still Hueffer), David Jones, Siegfried Sassoon, Frederic Manning, et alii.
From all these and more, Anne Powell has stitched together a moving narrative both in prose and verse.