The biography, based on 10 years of archival research and interviews with people in Mao’s inner circle, is a stunning challenge to China’s conventional view of the Communist leader.

The book estimates that Mao caused the deaths of 70 million people in peacetime, making him a far worse killer than Hitler or Stalin. It portrays him as a sociopath who loved killing and allowed millions of peasants to starve to death while he exported food to pay for his nuclear weapons; a man whose legendary achievements in the Long March were an invention; a man who turned China into a cultural desert of misery and violence, while maintaining dozens of luxury villas and a troupe of female sexual partners.

One of the book’s two authors is Jung Chang, the Chinese writer whose family memoir, Wild Swans, became one of the biggest-selling non-fiction books of all time. Her co-author is her husband, Jon Halliday, a historian who gained access to Soviet archives on Mao.

Their 814-page biography, Mao: The Unknown Story, is to be published in Canada and the United States in October. The book is already a bestseller in Britain, where critics have hailed it as a major work. A Chinese translation is planned, although the Chinese edition is unlikely to circulate outside Taiwan and Hong Kong.

China’s rulers have acknowledged that Mao made some ‘serious mistakes,’ but only ‘in his old age.’ And they continue to praise him lavishly, decades after his death. ‘Comrade Mao Zedong was a great Marxist; a great proletarian revolutionary, strategist and theorist; a great patriot and national hero,’ President Hu Jintao said on the 110th anniversary of Mao’s birth in 2003.

The new biography, however, paints Mao as bloodthirsty tyrant who was never interested in Marxism or helping China’s impoverished peasants, but was obsessed only with personal power and military dominance. He rose to power because of his ruthlessness and cruelty, and because he was installed and financed by Moscow. Beginning with his earliest purges, in which he ordered the torture and death of thousands of Red Army soldiers in 1929, he believed in violence.

As early as 1927, the biography says, Mao was lauding China’s peasant associations for their use of terror and torture to break down the dignity of their enemies. He exulted that their violence was ‘wonderful’ and ‘a kind of ecstasy never experienced before.’

After seizing national power in 1949, Mao launched a brutal campaign that killed three million ‘counter-revolutionaries.’ Executions were usually done in public. ‘His aim was to scare and brutalize the entire population, in a way that went much further than either Stalin or Hitler, who largely kept their foulest crimes out of sight,’ the authors write.

By the late 1950s, Mao was starving his people to pay for his dream of making China a nuclear-armed superpower. He treated the peasants as dehumanized slave labourers, feeding them less than Auschwitz death-camp inmates. The authors estimate that during the Great Leap Forward, almost 38 million Chinese died of starvation, the worst famine in recorded history.

Another three million people died violent deaths in the Cultural Revolution, and Mao enjoyed seeing films of his enemies being tortured and humiliated, the authors say. In some provinces, the killings reached such a frenzy that cannibalism was practised.

Throughout all of this, Mao repeatedly told his aides that he was willing to let half of China’s population die for the cause of world revolution and his superpower dream.

Hundreds of thousands of landlords were exterminated in the early 1950’s. From 1959 to 1961 probably 30 million people died of hunger — the party admits 16 million — when Mao’s economic fantasies were causing peasants to starve and he purged those who warned him of the scale of the disaster.

Many more perished during the Cultural Revolution, when Mao established a special unit, supervised by Prime Minister Zhou Enlai, to report to him in detail the sufferings of hundreds of imprisoned leaders who had incurred the chairman’s displeasure.

One of the chairman’s secretaries, Li Rui, wrote recently, “Mao was a person who did not fear death, and he did not care how many were killed.” The writers of the Kaifang article tell us what this meant for China: “Mao instilled in people’s minds a philosophy of cruel struggle and revolutionary superstition. Hatred took the place of love and tolerance; the barbarism of ‘It is right to rebel!’ became the substitute for rationality and love of peace. It elevated and sanctified the view that relations between human beings are best characterized as those between wolves.”

It is common in academic circles, not only in China but in the West, to consider Mao as a thinker, guerrilla leader, poet, calligrapher and literary theorist. Mao specialists tend to divide his career into two periods: before 1957, when Mao “the visionary” fought his way with tenacity and brilliance to party leadership and set about transforming China from a fragmented, backward society into a unified nation; and after 1957, in which Mao became power-crazed and dragged China into violence and economic stagnation.

The signatories of the Kaifang broadside, however, see Mao whole: “Under Mao, the ideological obsession with ‘attacking feudalism, capitalism and revisionism’ severed links with traditional Chinese culture, with modern Chinese culture and with Western civilization, deliberately placing the country beyond the mainstream of human civilization.”

This seems reasonable. Yet few of Mao’s closest comrades, or their successors today, ever admitted publicly, even after his death, that from his earliest years of authority whatever Mao proposed, encouraged or commanded was underpinned by the threat of death. This was also the secret of Stalin’s power, and of Hitler’s. The Kaifang writers note that “Mao Zedong’s writings poisoned the soul and the language of the Chinese race; and his violent, hate-filled, loutish language remains a problem to this day.”

In 1973 Mao suggested, apropos of Hitler, that the more people a leader kills, the more people will desire to make revolution. Mao would have approved the killing of unarmed protesters in spring 1989 not only in Tiananmen but in dozens of cities throughout China, and would have hailed the party’s “hate-filled” insistence to this day that the 1989 demonstrators were criminals who deserved what they got.