How Accurate Is Killers of the Flower Moon?
Updated 2026-09-23
A real conspiracy to murder Osage people for their oil money, told largely as it happened
Killers of the Flower Moon (2023) is one of the more faithful historical films of recent years. The murders of wealthy Osage people in Oklahoma in the early 1920s, the scheme run by the cattleman William Hale, the marriage of Ernest Burkhart and Mollie Kyle, and the poisoning of Mollie all happened. The film is based on David Grann's 2017 book of the same name.
Its biggest change is one of point of view. Grann's book is framed around the Bureau of Investigation agent Tom White, who solved the case. Martin Scorsese and Eric Roth rewrote the script after meeting members of the Osage Nation, who kept returning to the marriage of Ernest and Mollie, and the film centres on that marriage instead.
What the film gets right
Why the Osage were targeted. When the Osage reservation was divided up, the tribe kept its mineral rights in common, and each Osage on the tribal roll received a share of oil royalties called a headright. When oil was found, the Osage became some of the wealthiest people per head in the world. A headright could pass by inheritance, including to a non-Osage husband, which gave killers a motive.
The guardianship system. Federal law placed many Osage under white guardians, and local courts routinely declared Osage people incompetent to manage their own money without any real assessment. The film's scenes of Osage adults needing a guardian's permission to spend their own money reflect a real and corrupt system.
The killings of Mollie's family. Mollie's sister Anna Brown was shot in 1921, her mother Lizzie Q died soon afterwards, and in 1923 the house of her sister Rita and Rita's husband Bill Smith was blown up with nitroglycerin. Henry Roan was shot by a hired killer, John Ramsey. All of these are real.
Mollie's poisoning. Mollie, who had diabetes, was being slowly poisoned while in Ernest's care, as the film shows. She survived.
The scale. At least 60 wealthy Osage people were reported killed between 1918 and 1931, and later research suggests the true number may have been in the hundreds. The film makes clear that Hale's ring was only part of a wider pattern.
What the film changes or leaves out
The investigators. The Bureau of Investigation, the forerunner of the FBI, began sending undercover agents in 1925 under Tom White and exposed Hale's ring. In the film they arrive late in the story and get little screen time, a deliberate choice.
Ernest's inner life. Much of what Ernest thinks and feels in the film is necessarily imagined, since the record shows what he did rather than why. The film presents him as weak and dominated by his uncle, which fits his eventual confession but is an interpretation.
Compression. Events spread over several years are compressed, and some minor figures are merged or left out.
Osage reactions. Osage consultants praised the filmmakers for listening, and Chief Geoffrey Standing Bear supported the project. Some Osage viewers still wished the film had told the story through Mollie's eyes rather than Ernest's, and the actress Devery Jacobs criticised the Osage characters as underwritten.
What happened afterwards
Ernest Burkhart pleaded guilty in 1926 and was sentenced to life in prison. He was paroled in 1937 and later pardoned by the governor of Oklahoma. William Hale was convicted and sentenced to life, paroled in 1947, and died in 1962. John Ramsey was also sentenced to life and paroled in 1947.
Mollie divorced Ernest, remarried, and died of unrelated causes on 16 June 1937. In 1925 Congress changed the law so that non-Osage could no longer inherit headrights from Osage people of half or more Osage ancestry, closing the loophole that had driven many of the killings.
Frequently asked questions
Is Killers of the Flower Moon a true story?
Yes. It is based on the real murders of Osage people in Oklahoma in the 1920s, as told in David Grann's 2017 book. William Hale, Ernest and Mollie Burkhart and most of the victims were real.
Did Ernest Burkhart really poison Mollie?
Mollie, who was diabetic, was slowly poisoned while in Ernest's care and survived. Ernest pleaded guilty in 1926 to his part in the murders and was sentenced to life.
How many Osage were murdered?
At least 60 wealthy Osage people were reported killed between 1918 and 1931. Later research suggests the real number may have been in the hundreds.
What happened to William Hale?
He was convicted and sentenced to life in prison, paroled in 1947, and died in 1962.
What happened to Mollie Burkhart?
She survived the poisoning, divorced Ernest, remarried and died of unrelated causes in 1937.
Why is the FBI barely in the film?
Director Martin Scorsese rewrote the script after consulting members of the Osage Nation to tell the story from the Osage community's side rather than through the investigators, who are central to David Grann's book.
What were Osage headrights?
Shares in the tribe's oil royalties, one per person on the tribal roll. They could be inherited, including by non-Osage spouses, which gave outsiders a motive to marry into and then kill Osage families.
Further reading
1. Killers of the Flower Moon — David Grann (2017)
The Osage murders were a wide conspiracy, and the solved cases were only a fraction of the killing.
The book the film is based on, and a gripping investigation in its own right.
Pick this if: Anyone who saw the film. (Level: Beginner)
2. The Underground Reservation: Osage Oil — Terry P. Wilson (1985)
Oil wealth transformed the Osage Nation and drew outsiders who exploited it.
The history of the oil money at the heart of the murders.
Pick this if: Readers who want the economic background. (Level: Advanced)
3. The Osage and the Invisible World — Francis La Flesche (ed. Garrick A. Bailey) (1995)
Traditional Osage religion and ceremony, recorded in the early twentieth century.
A window into the Osage culture the film tries to portray from the inside.
Pick this if: Readers who want the Osage world beyond the crimes. (Level: Advanced)
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Sources consulted
Researched with AI and verified against mainstream scholarship and the cited sources on this page. See our methodology and corrections policy.
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