Chinese authorities have largely whitewashed the more brutal and tragic episodes in their history since the Communist Party took power in 1949.

The Cultural Revolution took place between 1966-1976 and plunged China into utter chaos, with more than 30 million people persecuted, tortured or killed.

It has been labelled a mistake, but it's never been officially discussed or investigated.

And while most Chinese families suffered, they don't openly talk about it.

Now one women is trying to reclaim a part of that history and get the Chinese Government to overturn the false conviction of her father.

Nicolai Tankin, now 93, was labelled a Russian spy at the height of the Cultural Revolution.

Nicolai (tallest at the back) with colleagues at the Beijing Foreign Language University in the 1950s. ( Supplied )

His daughter Lucille Tankin now lives in Australia, but she has returned to Beijing several times to fight the Chinese courts and a Government that refuses to confront its ugly past.

She knows it's an uphill battle, but she is determined to wage it.

"[During the] Cultural Revolution they did a lot of things to a lot of people. I'm not the first or the last. I'd like to know what happened and I want some answers," she said.

Easy targets for the revolution

Nicolai was one of the founders of the Russian Language Department at the Beijing Foreign Language University in the 1950s.

He was of mixed Chinese and Russian descent and his wife Lydia was Russian. Together they had five children.

The Cultural Revolution took place between 1966 and 1976, plunged China into utter chaos. ( Wikipedia )

The family was already under suspicion when Soviet-China relations started to sour in the late 1950s, but with the onset of the Cultural Revolution they became easy targets.

The university, like all others in China, was effectively shut down and taken over by the students.

The family lived on the campus and Lucille says she still has vivid memories of those time.

"There was no rules or regulations, the students were running the university. It was absolute chaos," she said.

"There was fighting and they were beating people up."

The family was labelled as a suspect class — intellectuals and foreigners, part of the old guard that had to be destroyed to restore "ideological purity".

Nicolai was convicted of trumped up charges of spying, providing information to the Soviet embassy and in 1969 he was sentenced to 13 years in prison.

Lucille said the whole family was then labelled as counter-revolutionaries. Her mother was taken and then the Chinese authorities came for the five children.

The original verdict accusing Nicolai of being a spy. ( Supplied )

'One by one they came for us'

The family was separated and broken up.

"They took my brother put him somewhere, I don't know where," she said.

"Then a couple of months later they took my oldest sister, then a few months later they took my second sister."

Lucille was only seven when she was taken. She lost any sense of a childhood.

"It was almost like a jail with 15 other women and girls," she said.

"We stayed there and every day we had to say what bad things we did and how we are going to change.

"I just said I didn't study hard enough on Mao's red book. I just had to make it up. Stupid things like that, nothing means anything.

"There was a girl in there who believed in Jesus and they put her on a chair and let her stand for hours while they threw allegations at her.

"Then she'd stand for so long her leg gave out and she fell down. They didn't bother about her bleeding head. They were just animals."

Fleeing to Australia

Nicolai and his wife Lydia just before leaving for Australia in 1978. ( Supplied )

After 10 years Nicolai was released.

The family was given one month to leave China and Australia granted them political asylum in 1978.

"When I saw him after 10 years he was shrivelled up and had white hair," Lucille said.

"He was broken, so beaten up within himself. He spoke quietly, almost whispering, like just in case anyone could hear him."

The Tankin family reunited after 10 years of imprisonment. ( Supplied )

After establishing a new life in Australia, Lucille then turned to pursuing justice for her father and her family.

She made several trips to Beijing and in 2016 she managed to obtain the original court ruling made against her father in 1975.

The family's lawyer in Beijing, David Zheng, examined the original verdict and said the court did not present any argument or evidence against Nicolai.

On this basis Mr Zhang has appealed to the National High Court.

He said they might have a chance as some of Nicolai's colleagues at the university have had their convictions overturned back in the late 1970s as part of the rehabilitation of the intellectual class.

"Seeing from what we know so far, Tankin was charged for two crimes, two of his colleagues were rehabilitated and their justice were restored," he said.

"We believe, for Tankin, if they could reinvestigate it there is a hope to overturn the previous verdict.

"However, the precondition is they could start the process of reinvestigation."

'Nobody wants to admit they were wrong'

Mr Zhang said the problem is the case is a political one.

The biggest hurdle is authorities don't want to admit in a court that they were wrong.

Lawyer David Zhang says the difficulty will be to get anyone to take responsibility for what happened. ( Reuters: Thomas Peter )

That would force them to confront the injustices done to millions during the Cultural Revolution and start an avalanche of claims that could increase resentment against the Communist Party.

Mr Zhang said the other difficulty will be to get anyone to take responsibility.

"There is a lot of buck passing, but we will continue to fight for justice," he said.

Under the background of the Cultural Revolution, foreigners or people with foreign backgrounds were attacked or cracked down upon.

"In Beijing Foreign Language Institute there were lots of foreign experts or scholars teaching," Mr Zhang said.

"Lots of them had similar experiences, they were denounced and struggled, some of them were thrown to jail for a very long time."

Nicolai Tankin's Chinese and Australian passports. ( Supplied )

Lucille will return to Beijing soon to continue the fight and to hopefully and finally deliver some peace to her father.

"I think he'll go to the grave a happy man," she said.

"All of this burden would be lifted because I see him [and] even now it's weighing him down.

"There's certain things he won't talk about. But he will be extremely happy, grateful if they could overturn his verdict."