Inside US’ ‘forgotten’ blood-soaked mass murder plot that inspired new Leonardo DiCaprio film Killers Of The Flower Moon

ON the face of it Mollie Burkhart had it all — a mansion, chauffeur-driven car and the rights to an oil field.

But being a member of the Native American Osage tribe, said to be the richest people per capita in the world in the 1920s, made her a target for a mass murder conspiracy.

Leonardo DiCaprio and Lily Gladstone in Killers Of The Flower MoonCredit: Alamy

Lily Gladstone as Mollie Burkhart, Robert De Niro as William King Hale and Leonardo DiCaprio as Ernest BurkhartCredit: Planet Photos

Ernest Burkhart’s scheming uncle William Hale, – played by DeNiro – convinced him to wed Mollie in 1917Credit: Planet Photos

One of Mollie’s sisters was shot in the back of the head and dumped in a ravine and another blown up as she slept after a five-gallon keg of explosive nitroglycerin was placed under her home.

Around the same time the young mother was being slowly poisoned by her non-indigenous husband in a plot to steal her fortune.

Mollie asked the fledgling precursor of the FBI to investigate the horrifying slayings.

Despite surviving poisoning after her priest warned her against touching the liquor at home, her sisters were among the first of what is believed to be around 100 Osage victims in what became known as the Reign of Terror.

Now this tale of greed and betrayal is being told in £160million movie Killers Of The Flower Moon by legendary director Martin Scorsese, starring A-listers Leonardo DiCaprio and Robert De Niro.

The film, which opens in cinemas on Friday before being streamed on Apple Plus, is already being tipped for Oscar success and has been described as a “masterpiece”.

DiCaprio, who plays Mollie’s treacherous husband Ernest Burkhart, wanted to make sure the world knew about this shameful part of his country’s past.

The 48-year-old said: “It’s a completely forgotten part of American history and an open wound that still festers.”

The Osage had been forced off their lands in Missouri and on to what was considered to be an impossible-to-cultivate reservation in northern Oklahoma in 1872.

Thunderous explosion

All it seemed to offer was the beautiful plants that bloomed into what they called “flower moon”.

Then 22 years later the largest deposits of oil and gas in the US were discovered underneath the reservation the tribe had bought.

They managed to fend off attempts by the government to grab their land and, by the 1920s, 2,000 of them were sharing annual royalties worth an estimated £300million in today’s money.

The Osage bought limousines etched in gold, sent their children to private school, learned ballet and had white servants.

With the rights to each plot abundant with “black gold” automatically passing on to relatives, white men started to see the financial advantage in marrying Osage women.

One was First World War veteran Ernest Burkhart, whose scheming uncle William Hale — played by DeNiro in the film — convinced him to wed Mollie in 1917.

Fraudster Hale was extremely powerful, controlling a bank and part owning a general store in the town of Fairfax.

Known as the King of Osage Hills, he had influence over local lawmen, who turned a blind eye to many of the suspicious deaths.

One of the first victims was Mollie’s sister Minnie, who died aged 27 from what doctors diagnosed as a “peculiar wasting illness”.

Such excuses could not be made when her other sister Anna, 25, was driven in an open top Buick to a quiet spot in the Osage Hills by Ernest’s brother Byron in May 1921.

Cold-hearted hitman Kelsie Morrison delivered a bullet to the helplessly intoxicated woman’s brain from behind.

On the same day Anna’s cousin, Charles Whitehorn, was also found to have been murdered, and less than two years later another cousin, Henry Roan, suffered the same fate.

Two months later, Mollie’s mother Lizzie Q Kyle was also killed.

Fearful locals hired bodyguards and private detectives.

But one of the gumshoes ended up badly beaten and a friendly oilman who offered to help the Osage was stabbed 20 times.

On the evening of March 10, 1923, Mollie was woken by the thunderous sound of the house of her only surviving sister, Rita, exploding in the settlement of Gray Horse where they both lived.

Rita, her husband Bill Smith and housekeeper Nettie Brookshire all died as a result of the powerful blast.

The explosives had been planted by assassin Asa “Ace” Kirby, hired by Mollie’s husband.

Yet no arrests were made, even though many people suspected Hale was behind the carnage because his nephew was in line to inherit the mining rights of the people who were dying.

Mollie Burkhart was a Native American Osage tribe memberCredit: Media Drum World

Mollie’s treacherous husband Ernest BurkhartCredit: Media Drum World

William King Hale was a wealthy Oklahoman cattleman known as the King of the Osage HillsCredit: Getty

Present day Oklahoma city mayor David Holt, who is an Osage descendant, said: “It was the subhuman way that Native Americans were treated.

“Not just that they were murdered, but that it wasn’t even hardly viewed as a crime that they were murdered.

“The perpetrators were allowed by local and state authorities to basically get away with it.”

Mollie, who did not suspect her husband was involved in the deaths or her attempted murder, went to the capital, Washington, to ask the authorities for help.

Finally, in 1925, after 60 contentious Osage deaths, The Bureau of Investigation’s director J Edgar Hoover sent a team of agents to Fairfax to bring the killers to justice.

A year later they amassed enough evidence for Hale to be convicted for Roan’s murder and to convince Burkhart to confess to plotting the deadly explosion.

Both men received life sentences but were released early from prison, with Hale only serving 18 years and Burkhart doing 11.

Burkhart’s granddaughter Margie, who met him before his death in 1986, has not forgiven him, saying: “I have a lot of anger towards him.

“He took away my whole family.

“He took away potential cousins.

“I don’t have any relatives on my Osage side.”

‘A great reckoning’

While the murders were largely forgotten by US society, they became infamous among all Native Americans.

Actress Lily Gladstone, who is being Oscar-tipped for her remarkable portrayal of Mollie, is from the indigenous Blackfeet Nation.

She says: “Dad told me about Osage people being murdered for their oil wealth.

“This isn’t that many generations ago, it is in very recent family history.

“It’s had a very lasting impact.”

Hale was almost certainly not alone in using deadly means to get his hands on the oil rights.

Lily continues: “It’s beyond the story that you see, the cases that were tried were a couple of dozen in the film, there were hundreds of Osage that were killed during this time.”

How many remains unclear.

The current Osage principal chief, Geoffrey Standing Bear, believes five per cent of the tribe’s then population were bumped off, which was more than 100 victims.

A popular method for dispatch was putting the poison strychnine in the target’s whisky.

Many others were swindled out of their inheritance by the officials placed in charge of their oil rights.

In 2011, following a lengthy legal battle, the US government agreed to pay the tribe more than £300million for lost assets.

Even now, there are ongoing disputes about the financial rights of the Osage people in Oklahoma, who now make around £60million from the gambling operations on their reservation on top of their income they continue to receive from oil and gas produced in the county.

One in six residents of the state is Native American and the current mayor is the second Native American to lead Oklahoma state.

Yet one in three Native Americans live in poverty and DiCaprio hopes that the movie will raise awareness of the inequalities that still continue.

He told British Vogue magazine: “We are coming towards a great reckoning of our past.

“The more that these stories can be told in a truthful way, the more it can be a healing process.”

For the Osage, who cut the image of Hale out of photographs because they consider him to be the devil, it will take more than a movie to change things.

A century on from the Reign of Terror, chief Standing Bear concluded: “My people suffered greatly, and to this day, those effects are with us.”

Killers Of The Flower Moon is in cinemas from Friday.