STEVE INSKEEP, HOST:
Generations ago, the Osage Indian Nation was forced to move. Not for the first time, white settlers pushed them off their land in the 1800s. The writer David Grann sees in that move the start of an astonishing and tragic story.
DAVID GRANN: When they were being driven off their land in Kansas, they didn't know where to go. And an Osage chief stood up and he said, we should go to this area that would later become northeast Oklahoma because it's rocky and infertile and the white man will finally leave us alone.
INSKEEP: It turned out the Osage had chosen land that was rich in oil. In the early 20th century, members of this beaten-down Indian nation grew spectacularly wealthy. They bought cars. They built mansions. They made so much oil money that the government began appointing white guardians to help the Indians spend it. And then the Osage started to be killed.
David Grann investigated their story for the new book "Killers Of The Flower Moon." He tells this half-forgotten story beginning with Mollie Burkhart, an Osage woman, in 1921.
What happened to her?
GRANN: So Mollie Burkhart's family - she had four sisters. And one day in 1921, her older sister disappeared. And about a week later, her body was found in a ravine. Mollie's mother, within two months, she, too, had died. And evidence later suggested that she had been secretly poisoned.
Not long after that, Mollie was sleeping in her bed. She heard a loud explosion. And she had another sister who lived not far away. And in the area where her sister's house was, she could see almost this orange fireball rising into the sky. And her sister's house had been blown up, killing that sister as well as her sister's husband and a servant.
INSKEEP: It's still a little hard to get your brain around how it is that someone could commit all these killings and then inherit their oil wealth. Who would be in a position to do that?
GRANN: What makes these crimes so sinister is that it involved marrying into families. It involved a level of calculation and a level of betraying the very people you pretended to love.
INSKEEP: You mentioned Mollie Burkhart.
GRANN: That's exactly what happened to Mollie. She had married a white man. And his uncle was the most powerful settler in the area. He was known as the King of the Osage Hills. And he had orchestrated a very sinister plot played out over years where he directed his nephew, who had married Mollie Burkhart, to marry her so that he could then begin to kill the family members one by one and siphon off all the wealth.
INSKEEP: How was this series of crimes investigated?
GRANN: So it's really important to understand back then that there was so much lawlessness. That was one of the things that shocked me when I began researching the story that even in the 1920s, much of America remained a country that was not fully rooted in its laws. Its legal institutions were very fragile.
Mollie Burkhart beseeched the authorities to try to investigate, to get help. But because of prejudice, they often ignored the crimes. And almost anyone who tried to investigate the killings, they, too, were killed.
One attorney tried to gather evidence. And one day, he was thrown off a speeding train, and all the evidence that he had gathered had disappeared. Another time, an oil man had traveled to Washington, D.C., to try to get help. He was then found stabbed more than 20 times. And finally a very - then very obscure branch of the Justice Department intervened. It was known as the Bureau of Investigation. And it was what would later be renamed the FBI.
INSKEEP: J. Edgar Hoover.
GRANN: J. Edgar Hoover. He was the new director. And it became one of the FBI's first major homicide cases that it ever dealt with.
INSKEEP: Did the agency that became the FBI solve these murders?
GRANN: The Bureau initially badly bungled the case. And J. Edgar Hoover was new in the job. And he was very insecure. He had dreams about building a bureaucratic empire. And he turned the case over to a frontier lawman, who put together an undercover team that included one of - probably the only American-Indian agent in the Bureau at the time. They were able, through some dogged investigation, to eventually capture some of the ringleaders.
INSKEEP: Are you telling me that the future Federal Bureau of Investigation established its reputation as great investigators by subcontracting it...
INSKEEP: ...Out to somebody who actually knew what they were doing?
GRANN: He did. They went to an old frontier lawman to help take over the case and they did a good job. But Hoover was desperate to wrap up the case. The Bureau missed a deeper and darker conspiracy that remained unsolved. And I think that's very important to understand.
INSKEEP: How do you know that?
GRANN: Well, many of the Osage began to point me in directions to other unsolved cases within their families going back. What this story really is about - it's not about a story of who did it. It's a story about who didn't do it. When I went to the National Archives in Texas, there was this little booklet. It had a little fabric cover. It - all it was was essentially identifying the name of a guardian and who - which Osage they were in charge of.
And when I began to look at the names of the Osage under them, I could see written next to many of them simply the word dead, dead, dead. You're beginning to realize you're looking at hints of a systematic murder campaign because there's no way all these people died in a span of just a couple years that defied any natural death rate.
And then when you begin to look into each of those individual case, you start to find trails of evidence of suggesting poisonings, a murder. You start to try to trace the money and where the wealth went. What you begin to discover is something even more horrifying than the Bureau ever exposed.
INSKEEP: When you've been poking around in this and revealing this information about a bunch of people's ancestors, what have people said to you?
GRANN: So one of the things that you realize when you spend time in Osage County is that the descendants of both the victims and descendants of the murderers still live there. They often live down the street from each other. And one Osage woman told me we try not to hold them accountable for what their ancestors did. Part of that is the story of America, this intertwining and this kind of reckoning with this original sin that is part of our formation of a country.
And I would say this, I spoke with some of the descendants of the husband of Mollie Burkhart and the uncle who was one of the masterminds of the plot. And they were remarkably candid. And after I finished the book, I received a note from one of the descendants who said, I'm so ashamed that this is part of our history. And please, if you see the Osage, will you please tell them that?
INSKEEP: David Grann is author of the new book "Killers Of The Flower Moon: The Osage Murders And The Birth Of The FBI." Thanks very much.
GRANN: Thank you.
(SOUNDBITE OF BRIAN BLADE AND THE FELLOWSHIP BAND'S "STATE LINES")