IT was the hub of the Holocaust, the scene too of some of the bitterest, most awful fighting of the Second World War.

Tens of millions died in the Soviet Union and the wider Eastern Europe in a matter of six years from 1939. Many victims were condemned to awful fates but the survivors faced further trials, the pain exacerbated by the dreadful realisation that liberation in the modern lexicon does not mean freedom and that a hunger of the body and the very spirit continued long after the depredations of the global conflict.

The first telling blow inflicted by Anne Applebaum's powerful, shocking book is the immediate depth of feeling by the reader for the survivor of Dachau, the ghetto or the front line who suddenly finds that further peril awaits at the hands of the liberator. This experience, of course, was not restricted to Eastern Europe. Tens of thousands of civilians died in France, for example, after the Allies landed on D-Day. They were viewed as collateral damage, sacrificed to the greater good of ending the conflict quickly.

However, Applebaum makes clear that those behind the Iron Curtain were victims of the peace, more precisely of an ideology that persisted for decades. These were people who lived in desperate times where the threshold of what was normal was base and unfeeling.

The imposition of a Stalinist communism on much of Eastern Europe is a vast subject. Applebaum cleverly disciplines the book by sticking to declared themes and mostly concentrating on the experience of Poland, Czechoslovakia and Hungary. This affords her work a feeling of order and academic thoroughness as she confronts the reality of politics, economics, youth, party structure and ethnic cleansing.

Applebaum, whose previous work, Gulag, is one of the best of modern histories, is familiar with the terrain and has the enviable facility to translate the minutiae of communist life into an expansive, comprehensible narrative. Invigorated by new archival material and with extensive interviews, this is a withering, dramatic indictment of totalitarianism. It is no incontinent polemic, however. This is a work that investigates ideas but, brilliantly, puts them into a human context.

At heart, this is a personal story, with Applebaum acting as ghost writer to a generation of lost victims. This is history that shouts of horror and injustice. Meet the Polish partisan who survived the Nazis but is condemned to the Gulag; meet the East German 16-year-old who starts a party to welcome "democracy" in the immediate post-war era and is sentenced as a war criminal; meet the 13-year-old Hungarian who is told he is "needed for a little work" and spends years in a labour camp.

The numbers of victims are so large as to be ungraspable: the 5558 suicides in Czechoslovakia in 1946, the 400,000 Volksdeutsche who died trying to escape from Poland to Germany, the 76,192 Ukrainians arrested in a few days in October 1947. The survivors of these experiences and many others hunkered down to communism. Applebaum describes their trials by using both records and personal testimony. Life under a totalitarian regime is thus authentically recreated with the populace bending under the unyielding power of the state.

Iron Curtain, in essence, is a book about fear. The rigidity of the state was based on the belief that any turning from the one true path would lead to an anarchy that would consume not only communism but, more relevantly, those in control. Those further down the hierarchy lived with fear as a daily companion. The ownership of a radio could mean a death sentence; an unguarded remark could entail a march to Siberia or any of the labour camps behind the Iron Curtain; strong protest almost certainly ended in death plus the dissident's family facing sanctions.

Much of the Iron Curtain, then, lived in what Applebaum describes as state of reluctant collaboration or passive resistance.

The book is so ambitious in scale that it seems almost petty to point out that revolutions of Hungary and Czechoslovakia are treated in a cursory fashion, though the author may argue that these subjects have been widely chronicled elsewhere. There is little on sport behind the Iron Curtain and this would have been an area worth investigation with, for example, the innovative drug-taking of East German athletes testifying to an all-pervading corruption.

However, these are quibbles, the mildest observations about a work that is intellectually rigorous and emotionally affecting.

In a world where people died in their millions, where injustice was a way of life, where daily uncertainty concerned whether one would spend the next night in prison or in a ditch, where art was intensely scrutinised for signs of dissent, only the joke survived, even prospered. The most telling is this:

"Who built the White Sea Canal?"

"Those who told political jokes."

"And who built the Volga-Don canal?"

"Those who listened."

Applebaum has listened and told the stories of those who can only survive as emblems of the destructive power of totalitarian regimes. The Iron Curtain has lifted in Eastern Europe but has descended elsewhere, notably in Syria. The ideology may have changed but the victims remain.