Difficult, very difficult.
Stalingrad, by Anthony Beevor, possibly.
Why – it's both chilling and compelling at the same time. Breathtaking in so many ways – from the scope of Hitler's territorial ambition, matched only by his incompetence and intransigence when meddling with field commanders freedom of operation; the brutality, indifference and connivance of Stalin's regime, through to the human capacity for outright animal brutality, suffering, survival and humanity.
A true, epic, Russian tragedy set in a relatively modern European context. Makes you realise either how far we've come, or how close we could be if we slipped back…