As the Chinese government tightened its grip over its ethnic Uyghur population, it sentenced one man to death and three others to life in prison last year for textbooks drawn in part from historical resistance movements that had once been sanctioned by the ruling Communist Party.

An AP review of images and stories presented as problematic in a state media documentary, and interviews with people involved in editing the textbooks, found they were rooted in previously accepted narratives — two drawings are based on a 1940s movement praised by Mao Zedong, who founded the communist state in 1949. Now, as the party’s imperatives have changed, it has partially reinterpreted them with devastating consequences for individuals, while also depriving students of ready access to a part of their heritage.

It is a less publicized chapter in a wide-ranging crackdown on Uyghurs and other largely Muslim groups, which has prompted the U.S. and others to stage a diplomatic boycott of the Beijing Olympics that open Friday. Foreign experts, governments and media have documented the detention of an estimated 1 million or more people, the demolition of mosques and forced sterilization and abortion. The Chinese government denies human rights violations and says it has taken steps to eliminate separatism and extremism in its western Xinjiang region.

The attack on textbooks and the officials responsible for them shows how far the Communist Party is going to control and reshape the Uyghur community. It comes as President Xi Jinping, in the name of ethnic unity, pushes a more assimilationist policy on Tibetans, Mongolians and other ethnic groups that scales back bilingual education. Scholars and activists fear the disappearance of Uyghur cultural history, handed down in stories of heroes and villains across generations.

“There’s much more intense policing of Uyghur historic narratives now,” said David Brophy, a historian of Uyghur nationalism at the University of Sydney. “The goalposts have shifted, and rather than this being seen as a site of negotiation and tension, now it’s treated as separatist propaganda.”

Sattar Sawut, a Uyghur official who headed the Xinjiang Education Department, was sentenced to death, a court announced last April, saying he led a separatist group to create textbooks filled with ethnic hatred, violence and religious extremism that caused people to carry out violent acts in ethnic clashes in 2009. He may not be executed, as such death sentences are often commuted to life in prison after two years with good behavior.

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Details about the textbooks were then presented in a documentary by CGTN, the overseas arm of state broadcaster CCTV, on what it called hidden threats in Xinjiang in a 10-minute segment. It included what amounted to on-camera confessions by Sawut and another former education official, Alimjan Memtimin, who got a life sentence.

The Xinjiang government and CGTN did not respond to written questions about the material.

Drawings from the textbooks are presented as evidence Sawut led others to incite hatred between Uyghurs and China’s majority Han population.

In one, a man points a pistol at another. The image is flashed over an on-camera statement by Memtimin, who says they wanted to “incite ethnic hatred and such thoughts.”

But both men in the drawing are Uyghurs. One, named Gheni Batur, holds up a gun to a traitor who had been sent to assassinate him. Batur was seen as a “people’s hero” in a 1940s uprising against China’s then-ruling Nationalist Party over its repression and discrimination against ethnic groups, said Nabijan Tursun, a Uyghur American historian and a senior editor at Radio Free Asia.

The Communists toppled the Nationalists and took power in 1949. Mao invited then-Uyghur leader Ehmetjan Qasimi to the first meeting of a national advisory body and said, “Your years of struggle are a part of our entire Chinese nation’s democratic revolution movement.” However, Qasimi died in a plane crash en route to the meeting.

Despite Mao’s approval, this period of history has always been debated by Chinese academics, Brophy said, and the attitude has shifted more and more toward hostility.

Another element in the story came to the fore after a series of knifings and bombings in 2013-14 by Uyghur extremists, who were angered by harsh treatment by the authorities.

The Uyghur movement had briefly carved out a nominally independent state, the second East Turkestan Republic, in northern Xinjiang in 1944. It had the backing of the Soviet Union, which had real control.

A recently leaked 2017 document, one of a trove given to an unofficial Uyghur Tribunal in Britain last September, shows that a Communist Party working group dealing with Xinjiang criticized elements of the uprising.

“The Three District Revolution is a part of our people’s democratic revolution, but there were serious mistakes made in the early stages,” the notice said.

Blaming interference by the Soviet Union, it said that ethnic separatists infiltrated the revolutionary ranks and “stole the right to lead, established a splitting regime, ... and committed the grave mistake of ethnic division.”

The document still said that Qasimi should be respected for his role in history.

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The CGTN documentary, though, singles out a photo of Qasimi wearing a medal that was the symbol of the second East Turkestan Republic. “It shouldn’t appear in this textbook at all,” Shehide Yusup, an art editor at Xinjiang Education Publishing House, said in the documentary.

Another textbook illustration, drawn from the same period, shows what appears to be Nationalist solider pointing a knife at a Uyghur rebel sprawled on the ground.

Both stories come from novels by Uyghur writers published by government publishing houses. One of the writers, Zordun Sabir, is a member of the state-backed Chinese Writer’s Association. The textbooks themselves were published only after high-level approval, said Kündüz, a former editor at the Xinjiang University newspaper who uses only one name.

When the textbooks were reviewed in 2001, the Uyghur stories hardly got any attention, said Abduweli Ayup, a Uyghur linguist who as a then-graduate student translated some of the stories into Chinese for the review.

Stories that portrayed the Nationalists as the enemy were not considered controversial. Instead, the Uyghur editors worried about foreign stories, said Ayup, an activist who now lives in Norway, such as a line from a Tolstoy story and a Hungarian poem.

Another story cited by CGTN goes back to the Qing Dynasty, which ruled China until 1912. Yusup, the art editor tells CGTN: “This is the legend of seven heroic Uyghur girls. It’s all fabricated. Han Chinese soldiers trapped them at a cliff and they jumped to their death to defend their homeland. It’s meant to incite ethnic hatred.”

But the soldiers were not Han, they were ethnic Manchu who founded the Qing Dynasty in 1644. The text of the story visible in the CGTN documentary says so, reading in part, “The Manchu soldiers started to climb Mount Möljer from all sides. Maysikhan (a leader of the Uyghur girls) saw the Manchus clambering up the mountain and told the girls to roll rocks down at them.”

The story is based on a local rebellion against the Qing Dynasty. A shrine dedicated to the seven girls stands in the Xinjiang city of Uchturpan, which partially funded it. Epics, articles and dramas about the story are popular.

“For the Chinese government to praise the uprising and then criminalize the inclusion of the story in textbooks is shocking,” Tursun, the historian said.

From even earlier, officials have been increasing the amount of instruction in Chinese in Xinjiang, especially after ethnic clashes in 2009 in Urumqi, the regional capital, said Minglang Zhou, an expert on China’s bilingual education policies at the University of Maryland.

Xi, as China’s leader, has stressed the consolidation of the nation, a move away from the “one unified nation with diversity” promoted by his predecessors, Zhou said. “He sees diversity as a threat to a unified nation.”

Kündüz lamented that her son, growing up in Urumqi, studied more in Chinese than in Uyghur. “They want to assimilate us, they want us to erase us,” she said from Sweden, where she now lives.

To this day, her son speaks Chinese better than Uyghur.