Alexander Solzhenitsyn, who first exposed the horrors of the Stalinist gulag, is now attempting to tackle one of the most sensitive topics of his writing career - the role of the Jews in the Bolshevik revolution and Soviet purges.
In his latest book Solzhenitsyn, 84, deals with one of the last taboos of the communist revolution: that Jews were as much perpetrators of the repression as its victims. Two Hundred Years Together
- a reference to the 1772 partial annexation of Poland and Russia which greatly increased the Russian Jewish population - contains three chapters discussing the Jewish role in the revolutionary genocide and secret police purges of Soviet Russia.
But Jewish leaders and some historians have reacted furiously to the book, and questioned Solzhenitsyn's motives in writing it, accusing him of factual inaccuracies and of fanning the flames of anti-semitism in Russia.
Solzhenitsyn argues that some Jewish satire of the revolutionary period "consciously or unconsciously descends on the Russians" as being behind the genocide. But he states that all the nation's ethnic groups must share the blame, and that people shy away from speaking the truth about the Jewish experience.
In one remark which infuriated Russian Jews, he wrote: "If I would care to generalise, and to say that the life of the Jews in the camps was especially hard, I could, and would not face reproach for an unjust national generalisation. But in the camps where I was kept, it was different. The Jews whose experience I saw - their life was softer than that of others."
Yet he added: "But it is impossible to find the answer to the eternal question: who is to be blamed, who led us to our death? To explain the actions of the Kiev cheka [secret police] only by the fact that two thirds were Jews, is certainly incorrect."
Solzhenitsyn, awarded the Nobel Prize for Literature in 1970, spent much of his life in Soviet prison camps, enduring persecution when he wrote about his experiences. He is currently in frail health, but in an interview given last month he said that Russia must come to terms with the Stalinist and revolutionary genocides - and that its Jewish population should be as offended at their own role in the purges as they are at the Soviet power that also persecuted them.
"My book was directed to empathise with the thoughts, feelings and the psychology of the Jews - their spiritual component," he said. "I have never made general conclusions about a people. I will always differentiate between layers of Jews. One layer rushed headfirst to the revolution. Another, to the contrary, was trying to stand back. The Jewish subject for a long time was considered prohibited. Zhabotinsky [a Jewish writer] once said that the best service our Russian friends give to us is never to speak aloud about us."
But Solzhenitsyn's book has caused controversy in Russia, where one Jewish leader said it was "not of any merit".
"This is a mistake, but even geniuses make mistakes," said Yevgeny Satanovsky, president of the Russian Jewish Congress. "Richard Wagner did not like the Jews, but was a great composer. Dostoyevsky was a great Russian writer, but had a very sceptical attitude towards the Jews.
"This is not a book about how the Jews and Russians lived together for 200 years, but one about how they lived apart after finding themselves on the same territory. This book is a weak one professionally. Factually, it is so bad as to be beyond criticism. As literature, it is not of any merit."
But DM Thomas, one of Solzhenitsyn's biographers, said that he did not think the book was fuelled by anti-semitism. "I would not doubt his sincerity. He says that he firmly supports the state of Israel. In his fiction and factual writing there are Jewish characters that he writes about who are bright, decent, anti-Stalinist people."
Professor Robert Service of Oxford University, an expert on 20th century Russian history, said that from what he had read about the book, Solzhenitsyn was "absolutely right".
Researching a book on Lenin, Prof Service came across details of how Trotsky, who was of Jewish origin, asked the politburo in 1919 to ensure that Jews were enrolled in the Red army. Trotsky said that Jews were disproportionately represented in the Soviet civil bureaucracy, including the cheka.
"Trotsky's idea was that the spread of anti-semitism was [partly down to] objections about their entrance into the civil service. There is something in this; that they were not just passive spectators of the revolution. They were part-victims and part-perpetrators.
"It is not a question that anyone can write about without a huge amount of bravery, and [it] needs doing in Russia because the Jews are quite often written about by fanatics. Mr Solzhenitsyn's book seems much more measured than that."
Yet others failed to see the need for Solzhenitsyn's pursuit of this particular subject at present. Vassili Berezhkov, a retired KGB colonel and historian of the secret services and the NKVD (the precursor of the KGB), said: "The question of ethnicity did not have any importance either in the revolution or the story of the NKVD. This was a social revolution and those who served in the NKVD and cheka were serving ideas of social change.
"If Solzhenitsyn writes that there were many Jews in the NKVD, it will increase the passions of anti-semitism, which has deep roots in Russian history. I think it is better not to discuss such a question now."