Famine is a frightful thing to contemplate, not least because we have the ability to contemplate it. If you have not experienced war, the veteran informs us, you have no idea of the reality of combat. But everyone can imagine, by mentally inverting our ordinary experience, how unpleasant it is to be forced to go without food. The word “famine” can induce chills in anyone.

Described by the economic historian Cormac Ó Gráda as “a shortage of food or purchasing power that leads directly to excess mortality from starvation or hunger-induced diseases,” a famine is one of the essential horrors of human experience, “the last, the most dreadful resource of nature,” in Malthus’s famous line. In the Bible, it is one of God’s most potent weapons in His campaign against sinners. In Ezekiel, He threatens to send “the evil arrows of famine” to destroy Jerusalem’s inhabitants (with “all thine abominations”). In Amos, He boasts of the ability to induce “cleanness of teeth in all your cities [i.e. hunger], and want of bread in all your places.”

It is not exaggeration to say that a human being within living memory possessed a God-like power to deploy famine against a populace that he expected to be “supernaturals of the first order.” During a four-year period from 1958 to 1962, Mao Zedong oversaw the deaths of about half of all the people who died during all of the famines of the twentieth century. In his haunting new book, Frank Dikötter carefully weighs the available archival evidence and “conservatively puts the number of premature deaths at a minimum of 45 million.” A minimum! In just one region (Xinyang) in one province (Henan) during one year (1960), one million out of eight million people perished, which is the exact proportion of deaths from the other “great” famine, the one in Ireland during the mid-nineteenth century that lasted for roughly five years. Unlike most famines—complex events caused by a confluence of natural, societal and political factors—there seems to be little debate about who is responsible for the carnage. One hesitates to commit blasphemy, but the Ezekielian God sounds a lot like Mao when he says, “I will bring the sword upon thee. I the LORD have spoken it.”

Mao’s famine was a consequence of a fantastical initiative, a “Great Leap Forward” into Communism, that he believed would turn China into an economic powerhouse, catapulting over its rivals in the Communist and non-Communist blocs. The idea was to use (and abuse) the country’s massive population—its most awesome resource—to boost agricultural and industrial output. The masses were stripped of private possessions, their homes and villages destroyed, and they were coerced into 26,000 giant “people’s communes” that were organized into military units.

The phrase “collective farm” does not quite capture what the communes were like. Since the battle for manufacturing supremacy could not be left to big factories in the cities—this was an intra-country competition with “a universe of norms, quotas and targets,” writes Dikötter—the communes were equipped with “backyard furnaces” that ‘Let All the People Smelt Steel!’ as the slogan had it. (In 1958, 140,000 tons of farming tools were tossed into the furnaces to boost production numbers.) But the communitarians were also responsible for increasing crop yields. They didn’t do this only by using the latest half-baked socialist farming techniques. They were also sent away from the fields by the millions to labor on massive irrigation, reservoir, and dam projects that were intended to turn arid land into fertile fields. Over several years, hundreds of thousands of weakened villagers died in doomed schemes—the huge Ming Tombs Reservoir was built in the wrong location, dried up, and was abandoned—that disturbed the ecological balance. In Fengyang, one of the counties most devastated by famine in 1961, floods were responsible for ruining crops even though the rainfall was basically normal that fall.

In his sickening hubris, Mao had meddled with centuries-old traditions of Chinese rural livelihood. Like Stalin did in the Ukraine in 1932-1933, he also used terror to exacerbate the suffering. When crop yields in the communes came up short, local party officials, terrified of being purged as 3.6 million others were during the Great Leap, fudged the numbers. Beijing then used these phony stats to determine how much grain should be expropriated from the farms (for the hungry in the cities, for impressionable governments in Cuba, Albania and elsewhere in the developing world, for the feasts that would mark the tenth anniversary of the Chinese Revolution in 1959, and so on). When the communes could not produce the food demanded by the state, rampaging cadres (themselves worried about being purged) were unleashed to find the grain hidden by those now branded “class enemies.” Dikötter estimates that 6 to 8 percent of the famine’s victims (at least 2.5 million people) were tortured to death or summarily killed by cadres.

Although Mao at first professed to be outraged by overzealous cadres, he nonetheless countenanced an increase in agricultural requisitions with the same penalties for those who failed to deliver them. Throughout the four years, his murderousness provoked little challenge or dissent from his senior advisors, who were trembling as violently as the rest of the party membership. Before an important meeting, Zhou Enlai spent days “in self-imposed isolation, struggling to find the right turn of phrase” to satisfy the boss’s mercurial temperament. Useful idiots such as François Mitterrand—who announced in 1961 that the “genius” Mao told him that there was no famine, just a “period of scarcity”—backed up the Chairman’s denials to the world. Only the mad told the truth. A survivor from Xinyang region described to Dikötter how a crazed man wandered their village repeating a jingle. “Man eats man, dog eats dog, even rats are so hungry that they nibble away at stones.” Everyone left him alone.

An apocalypse had descended. The commune canteens, which were overseen by the local thug-ocracy, distributed the only food that was permissible to eat. The Chinese people became so desperate that they ate anything they could scavenge, including toxic fish, plants, and animals (Mao’s countryside was rife with industrial pollutants), bloated corpses (which, after all, contained flesh), and even indigestible substances such as a soft mud called Guanyin. “Once eaten the soil acted like cement, drying out the stomach and absorbing all the moisture inside the intestinal tract,” Dikötter matter-of-factly reports.

Dikötter is extremely careful with his evidence. He does not flinch from telling the worst of the horrors: the abandonment of children, the sexual violence against women, the killing spree against “slackers, weaklings or otherwise unproductive elements.” Unlike most other famines, in which infectious diseases are typically the largest cause of death, significant numbers died from actual starvation in Mao’s inferno. (It was little consolation that the hands-on regime proved itself able to stop the spread of the notorious famine killer, typhus.) Dikötter estimates that from one million to three million people opted to grant themselves a small measure of power and end their lives by their own hand, which surely qualifies as the greatest mass suicide in history.

Dikötter succeeds in his dark task of cataloguing the awesome scale of the crime—China was truly gripped by a spirit of gigantism during the Great Leap Forward—but admits that the “full picture…will be known only once the Central Party Archives in Beijing open their doors to researchers.” In his book about what he called the “secret” famine, journalist Jasper Becker visited Xinyang, the scene of what a party official at the time of the famine called “a holocaust and massacre,” and found that few wanted to “remember Xinyang’s bitter history or to try to understand what happened there.” It is typical of those lucky enough to survive a famine: a powerful sense of shame. In Jeremiah, after God sent “black unto the ground” of Jerusalem, He describes the people as becoming “ashamed and confounded.” This partially explains why the tale remains a largely untold one. As a Chinese official said of the Great Leap Forward dams that would collapse decades after being built, “The crap from that era has not yet been cleared up.”

Peter Duffy is an author and journalist in New York.