Yet, 45 years after his death, a controversial new Russian book claims that Stalin acted "entirely rationally" in executing and imprisoning millions of people in Gulag labour camps in remote areas of Siberia. And, what's most shocking is that the book actually justifies tyrant Stalin's acts, saying "he did what he did to ensure the country's modernisation".

The book, a sort of teaching manual, titled 'A History of Russia, 1900-1945', is to be the latest guide for teachers to promote patriotism among the Russian youth and would form the basis of a school text book , the Daily Mail reported.

It may be mentioned here that at the end of the 1930s, Stalin launched a campaign of political repression. Millions of people who were a threat or suspected of being a threat to the Soviet politics were executed or exiled to Gulag labour camps, where many died of malnutrition, disease and exposure.

Historians estimate up to 20 million people perished as a result of his actions -- more than the six million killed during Hitler's genocide of the Jews. But, the manual says that the Great Terror of the 1930s came about as Stalin "did not know who would deal the next blow, and for that reason he attacked every known group and movement, as well as those who were not his allies".

The book emphasises that "it's is important to show that Stalin acted in a concrete historical situation" and that he acted "entirely rationally" -- as the guardian of a system, and as a consistent supporter of reshaping the country into an "industrialised state".