“Killers of the Flower” “Moon ”True Story: All About the Real Events That Inspired the Martin Scorsese Film

The film tells the true story of a series of brutal murders of wealthy Native Americans in the 1920s

Warning: This article contains spoilers for Killers of the Flower Moon, in theaters now.

Directed by the legendary Martin Scorsese, Killers of the Flower Moon tells the true story of the Reign of Terror, a series of brutal murders of members of the Osage Nation, who were the richest people per capita in the world in the 1920s.

The movie stars Oscar-winning actor Leonardo DiCaprio as Ernest Burkhart, a white man who comes to Oklahoma and marries a wealthy Osage woman named Mollie (played by Lily Gladstone) and becomes part of a conspiracy to murder members of her family in an effort to inherit her oil rights. The plot was concocted by William K. Hale, a wealthy cattle rancher and Burkhart’s uncle, who is played by Oscar winner and longtime Scorsese collaborator Robert De Niro.

The film — which is based on David Grann’s non-fiction book of the same name — brings the story of the Osage to the mainstream. Here everything to know about the real events that inspired Killers of the Flower Moon: 

Related: Granddaughter Recalls Killers of the Flower Moon Villain Played by Leonardo DiCaprio: 'Took Away My Family'

Who are The Osage?

The Osage Nation is a Native American tribe that originated in the Midwest. In the 19th Century, the U.S. government forced the tribe to move to Oklahoma, losing 95 percent of its population in the process, according to the Osage Nation Foundation.

But in 1894, oil was discovered on Osage land, and in 1906, the tribe retained the mineral rights to the oil, leading to an influx of millions of dollars and making the Osage Nation extremely wealthy.

The oil wealth of the Osage Nation also brought difficulties, though. Many tribe members were preyed upon by opportunists and murderers seeking to steal their fortune. The government also made it difficult for the Osage people to access their money.

According to David Grann’s book, many full-blooded Osages were designated “incompetent,” and a White guardian was appointed to oversee their fortunes. That meant if a wealthy member of Osage Nation wanted to go to the store and buy groceries, they would have to first meet with their guardian and get any expenditures approved.

In the movie Killers of the Flower Moon, main character Mollie Burkhart is shown meeting with a White guardian in order to access her wealth in order to buy food and even medicine.

Who were Mollie and Ernest Burkhart?

Mollie Kyle was a member of an Osage family that possessed oil headrights. Along with her mother, Lizzie Q. (played by Tantoo Cardinal), and sisters Minnie (Jillion Dion), Anna (Cara Jade Myers) and Reta (JaNae Collins), Mollie was quite wealthy.

In 1917, Mollie married Ernest Burkhart — a White man originally from Texas who came to live with his uncle — William Hale. They met, in real life and in the movie, when Ernest drove her in his cab. They soon fell in love.

Mollie and Ernest had three children, Elizabeth, James “Cowboy,” and Anna, the latter of whom died as a child after contracting whooping cough.

Who was William Hale?

William King Hale was a White cattle baron in Osage County, Okla., who had massive influence on the politics of the region and was one of the richest people, according to Grann’s book. Hale was also ingrained in the Osage community and considered himself a friend of the tribe. He was known as the “King of Osage Hills.”

In the film, Hale is shown to be close friends with Henry Roan (William Belleau), a member of Osage Nation who was murdered. The same was true in real life, according to the book, with the mayor of Fairfax saying at the time that “Roan considered W.K. Hale his best friend.”

Despite this, Hale masterminded a plot to kill Osages and inherit their oil rights, enlisting his nephews, Ernest and Byron (Scott Shepherd), and multiple others to carry out his plan.

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What was the Reign of Terror?

The Reign of Terror began in the 1920s, when a number of people in Osage Nation began dying mysteriously.

The murders were carried out by opportunists after the oil fortune. Osage oil rights could only be inherited, rather than purchased.

The family at the center of the film is Mollie Burkhart’s. In 1918, her sister Minnie died of a mysterious “wasting illness” that also claimed the lives of other Osages around this time. Mollie’s suspicions increased when her sister Anna, was found shot to death in a remote ravine in Osage County in 1921. Their mother, Lizzie Q., suspiciously died months later. In 1923, another sister, Rita, died when her house was bombed. Their oil rights were inherited by Mollie and Ernest, which Hale intended.

The true number of Osages killed during the Reign of Terror isn’t known, Grann says, but it could have potentially been in the hundreds.

“The Osage had countless millions of dollars stolen from them,” Grann tells PEOPLE. “Many lives were lost.”

How did the Reign of Terror End?

In the early years of the Reign, corrupt local authorities refused to properly investigate the crimes. As a result, Hale would help Mollie hire a private investigator to look into Anna’s death.

But after the death of Rita, and pleas from the Osage Nation for the federal government to investigate, a newly appointed director J. Edgar Hoover of the Bureau of Investigation, which would become the FBI, sent special agent Tom White (played by Jesse Plemons) to Osage County in 1925.

Authorities suspected Hale and Ernest, and the investigation turned when the latter finally confessed to his crimes. Ernest testified against his uncle in court and both were convicted of murder.

A key scene in the movie shows Ernest decide to stop lying about his involvement after the death of his daughter, Anna. According to Grann’s book, her death was indeed a pivotal moment.

Ernest was eventually paroled and later pardoned, while Hale was released from prison in 1947 despite having been sentenced to life in prison for first-degree murder. Hale died in 1962 and Ernest in 1986.

Related: Killers of the Flower Moon Cast Discuss Using 'Authentic' Osage Language in New Clip (Exclusive)

Did Ernest try to kill Mollie?

The film heavily implies that Mollie, a diabetic, was being poisoned to the point where she became increasingly sick as the years went by.

The Shoun Brothers (played by Steve Witting and Steve Routman), who were doctors connected to Hale, are shown in the film giving her what they say is insulin, but it makes her bedridden and pushes her to the verge of death. Ernest, who administered her shots, insisted that she keep taking them. It’s not until she’s taken into the care of other doctors that she starts to recover in the film.

Grann says that in real life, authorities believed she was given something to be kept quiet during the murders, though it’s uncertain if Ernest had any knowledge of it. In the film it’s deliberately kept vague if Ernest knew.

Margie Burkhart, the granddaughter of Mollie and Ernest, believes that in spite of everything, her grandfather actually loved her grandmother.

“They couldn't understand why she loved Ernest and Ernest loved her, and they couldn't understand that relationship,” Margie tells PEOPLE. “I guess nobody can.”

After Ernest pleaded guilty, Mollie, who knew nothing of the sinister plot, divorced him and never spoke his name again. She would later remarry and, according to the book, was restored to “competency,” meaning she was able to have full control over her money.

Mollie died in 1937.

The Apple Original Film Killers of the Flower Moon is in theaters, including IMAX® theatres, now.

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