In my case I read the book years ago because a distant relative was a tunneller (coalminer) who was one of those portrayed in the recent Australian film 'Beneath Hill 60". I had read a review of Birdsong, I think in the monthly journal of our National War Museum, that claimed it gave a very moving and factual recounting of the life of the tunnellers beneath the trenches. The book does this very well and I would have liked to have seen more of it in the film, particularly the tremendous stress and tension they were under as they neared the end of the tunnel knowing that the enemy was also nearing the end of his. Who would blow their charges first ??? Them or us. No wonder the survivors came home and suffered for years from their experiences.
But of course both the film and the book are about a Love Story set against the background of a time gone by and the War to End All Wars.