In the year or so that I have been working on a history of Stalin’s concentration camps, I have cried three times. Once when I read Eugenia Ginsberg’s account of the months she spent working in the children’s section of a camp, where the barbed wire, gates and guards formed a terrible contrast with the smell of ‘milk soup and wet diapers’. Another time I was so upset by the tale of a woman who was sent to Siberia in the tsarist era that I couldn’t work any more that day.

The third time was on reading Janusz Bardach’s account of his experience as an unwilling ponyatoy, a civilian witness who accompanied the NKVD – predecessors of the KGB – on their midnight rampage through his town in what had been Poland but had become, after the Soviet invasion of 1939, Western Ukraine. Bardach’s experience occurred in December, a few months after the Red Army had occupied the town, on one of the many nights when the NKVD were carrying out mass deportations. Picked up by a group of officers while opening the door to his flat, he was forced to witness a raid which included rape, murder, and the arrest of his friends and acquaintances.

At the home of some friends of Bardach’s parents, the chief officer ‘stormed through the house, swinging randomly at the furniture, paintings and candelabras, destroying the home where I had spent a great part of my childhood’. At another home, he watches as one of the officers picks up a