Is Killers of the Flower Moon a true story?

The movie unfolds mainly from the perspective of World War I veteran Ernest Burkhart (Leonardo DiCaprio), his Osage wife Mollie (Lily Gladstone), and his uncle William Hale (Robert De Niro).

But what really happened to Ernest and the other characters at the centre of the film? Read on for everything you need to know about the real history behind the Osage murders.

Killers of the Flower Moon true story

The events that are depicted in the film are based on real events that had previously been written about in Grann's meticulously researched book.

As is shown in the film, a huge number of Osage people and some of their allies were murdered in a plot organised by prominent white officials to steal their wealth – with the official death toll standing at over 60 but the actual total believed to be far higher.

While the victims were often murdered using different methods – some were shot, others poisoned over many months, others blown up in their own homes – nearly all of them were linked by the fact they had headrights earning them significant sums of money, or that they had become aware of information pointing to an organised plot.

Even before the murders began, government forces had made it extremely difficult for the Osage people to access their wealth, with many of their bank accounts controlled by guardians assigned by the state.

This climate saw the Osage population rendered powerless in the face of corrupt white professionals – from lawmen to doctors and politicians to business owners – and is part of the reason why the murders were allowed to go unreported and unsolved for so long.

Indeed, some of the early 'attempts' to solve the case were deliberately obfuscated by those responsible for the murders, who ostensibly hired private detectives to find the killers but were actually just attempting to cover their tracks.

Of course, even with the film's three-and-a-half-hour runtime, the conspiracy was so wide-ranging that it would have been impossible to include every single detail.

Therefore, rather than focusing primarily on the investigation by Bureau of Investigation agent Tom White (Jesse Plemons), which is given significant attention in the book and was the main focus of the original script, the perspective is shifted to the relationship between Mollie Burkhart and her husband Ernest.

Ernest was the nephew of William Hale, a man of significant standing in the local area who it later emerged had organised several of the murders, and Ernest himself was one of his key accomplices who was eventually persuaded to confess to his crimes and testify against his uncle.

In an exclusive interview ahead of the release, casting director Ellen Lewis explained to RadioTimes.com why the decision had been made to focus the film on the relationship between Ernest and Mollie – whose mother and sisters were among those to be murdered.

"It's already a very important story, a very painful story, a painful chapter in the history of my country. And [it became] that much more moving being told as that love story between Ernest and Mollie, rather than being told about the murders and tracking down," she said.

"And I think Marty has said this. I mean, everyone's culpable, but it definitely did give a different focus."

Although the film mainly centres on the crimes that can be directly attributed to Ernest Burkhart and William Hale, Grann's book features a final section revealing that even after their arrests, a number of murders continued to occur.

As such, although these two men undoubtedly bore huge responsibility for what became known as the 'Reign of Terror', this was actually just one part of the story, and the sheer scale of the plot was even greater.

What have the Osage Nation said about the film?

Speaking about the film and its accuracy to true events, the Osage Nation’s Principal Chief Geoffrey Standing Bear recounted a meeting with Martin Scorsese early in the process that allowed him to voice some concerns about the project.

"I didn’t want the Osage shown as just a bunch of bodies lying around," he said. "We were hoping the history and culture would be accurately represented in his movie.

"Mr Scorsese was so respectful in the way he and his people came to us. And he pointed out some of the movies he had made, in particular Silence, in which the cultures of Christian missionaries and 17th century Japan were presented in a serious and respectful manner, and that was so encouraging.”

Meanwhile, producer and researcher Marianne Bower spoke with many Osage people to ensure a level of respect and accuracy with how the culture was portrayed, with Elders from the community – including some whose family members had been victims of the Reign of Terror – among those to be consulted.

Marvin Stepson – whose grandfather Bill was murdered – is quoted as telling Scorsese and his team: "You have a difficult task in front of you. But I’m sure you will tell a great story, and that’s what we want to see — a great story, to tell the truth as best as it can be told.”

Killers of the Flower Moon is released in UK cinemas on Friday 20th October 2023. Check out more of our Film coverage or visit our TV Guide and Streaming Guide to find out what's on.

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