Immured behind an iron curtain for the whole of their sixty-year existence, the Soviet concentration camps have never been as well known in the West as their much shorter-lived Nazi equivalents. Detailed accounts first started making their way out in the Sixties, in the form of fiction – Solzhenitsyn’s Day in the Life of Ivan Denisovich – and a handful of survivor memoirs. Though the overall numbers – how many camps were there? How many people were in them? – could only be guessed at, the on-the-ground picture, of hard labour, relentless cold and hunger, and violent guards, seemed clear. Twenty years after the Soviet Union’s collapse, the numbers are fairly firm. About 18 million people passed through the Gulag (the acronym stands for Glavnoye Upravleniye Lagerei, or Main Camp Administration) between the start of its great expansion in 1929 and Stalin’s death in 1953, and upwards of 2.8 million, including exiles, died in it. But we are only now comprehending what was in reality a wide variety of individual Gulag experiences, dependent on when and where one was imprisoned, how well or badly one’s camp was run, and most of all, on one’s usefulness to the camp authorities.