Leonardo DiCaprio and Lily Gladstone as Ernest and Mollie Burkhart.Photo:Melinda Sue Gordon/Apple

Killers of the Flower Moon

Melinda Sue Gordon/Apple

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

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

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 theOsage 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.

Pawhuska, Okla.Oklahoma Historical Society/Getty

Photograph of a half-tone postcard, Pawhuska, Oklahoma, 1906.

Oklahoma Historical Society/Getty

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 movieKillers 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 Burkhart.Bettmann Archive/Getty

Bettmann Archive/Getty

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.”

William K. Hale, center.Bettmann Archive/Getty

William K. Hale, the mystery man of Oklahoma, who is on trial here for the third time in connection with the death of Dewey Roan, Osage Indian and Ward of the government. The picture shows, left to right, Mrs. William Oller, daughter of Hales, the accused man, and Mrs. Hale.

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.

For more on the true story behindKillers of the Flower Moon, pick up the latest issue of PEOPLE, on newsstands Friday, or subscribehere.

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 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.”

Lily Gladstone and Leonardo DiCaprio as Mollie and Ernest Burkhart.Melinda Sue Gordon/Apple

Lily Gladstone and Leonardo DiCaprio in Killers of the Flower Moon

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.

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.

Did Ernest try to kill Mollie?

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.

Robert De Niro, left, and Leonardo DiCaprio as William Hale and Ernest Burkhart.Apple Tv+

Leonardo DiCaprio Talks Importance of Being ‘Authentic’ in Killers of the Flower Moon Featurette

Apple Tv+

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 FilmKillers of the Flower Moonis in theaters, including IMAX® theatres, now.

source: people.com