By the 1870s, the Osage Indians had been driven from their land in Kansas to a rocky and barren stretch of northeastern Oklahoma.

Decades later, their new home was found to contain one of the richest reserves of oil in the United States.

Suddenly, the Osage were rich beyond their wildest dreams — and, almost as suddenly, they began to be killed.

In his new book, “Killers of the Flower Moon: The Osage Murders and the Birth of the FBI,” New Yorker staff writer David Grann details the conspiratorial crimes — specific families were targeted and the rights to their land passed to wealthy or prominent Oklahomans — and how a former Texas Ranger and the fledgling FBI cracked the case.

Grann, whose narrative nonfiction book was released last week, will appear Wednesday for the “Evenings With Authors” series, hosted by the Thurber House. Grann, who also wrote the nonfiction books “The Lost City of Z” and “The Devil and Sherlock Holmes,” spoke recently by phone with The Dispatch.

Q: How did you learn of the Osage murders and get started on this story?

A: I had heard about it in 2011 from a historian. ... I was kind of shocked that I hadn’t heard about it in school. I visited the Osage Nation in Oklahoma. The first time I was at their museum, I noticed this large panoramic photo of the tribe. There was a panel missing, and I asked the director why, and she said there was a figure in the missing panel — the devil was standing right there. Then she went into the basement and brought up a photo of the missing panel with one of the murderers in it. That was a turning point for me. I really wanted to know who this figure was.

Q: Why is this story — which is so compelling — so unknown in the United States?

A: It’s kind of amazing how its been excised from the American consciousness. I don’t know exactly why. The case was known at the time and (FBI Director J. Edgar) Hoover promoted it, but then he moved on to promote other cases. I think many of the murders were covered up and neglected because of prejudice.

Q: How long did it take you to research and write this book?

A: Nearly half a decade. It took me a long time to find the tribal material and track down the descendants. One of the things that was important to me in telling this story was to make sure the victims had a voice.

Q: How are the residents of Osage County doing today?

A: I don’t like to speak for other people, but they have a very vibrant community. Much of their oil wealth was stolen, pilfered — and a good deal was lost during the Depression, and the oil reserves have been depleted, so it’s not like the 1920s when millions and millions of dollars were flowing.

Q: What kind of feedback have you gotten from them?

A: I’ve received some very nice comments. In the many years I spent there, I realized they knew their history intimately and that their history hadn’t been part of the broader history. They were very generous and helpful in sharing their information to help bring this story to light.

Q: Some of the Osage married non-Indians and actually had murderers in their own families, didn’t they?

A: Right. One of the central figures in the book is a family member who was complicit in the murders. A granddaughter had a photograph that showed her father as a little kid. (In the photo), the face of another family member had been ripped out because he was one of the killers.

Q: You write true stories that are filled with intrigue. How do you sniff out these tales?

A: I think it’s the usual ways of reading and talking to people. I think the hardest part is finding a story worth telling ... and one that hadn’t been told before. The most tantalizing ideas come from those 1-inch briefs in newspapers. I have systems of rotating in regional newspapers to see if I can find something, but with the state of newspapers these days, the metro sections are getting slimmer and slimmer.

Q: Do you read crime fiction?

A: I do. I love detective stories. I grew up with Sherlock Holmes. I’ve always been fascinated with fiction and true stories about crime. I think of reporting as an extension of that — sifting through facts and finding threads and making sense of some of the chaotic elements of life.

I read so much nonfiction, so I read crime fiction for pleasure: Michael Connelly, Kate Atkinson, Tanya French, George Pelecanos.

Q: How do you plan to talk about “Killers of the Flower Moon” during your appearance?

A: I have an amazing database of archival photographs. I want to talk about the story and use photography to kind of walk people through it, so they can visualize it: The history of the Osage and where their money came from and how the rest of the country responded to the Osage’s wealth, and then talk about the deeply sinister conspiracy and the impact today on the people.

This story has so many twists and turns, and, ultimately, it’s a story of good and evil. The evil is so startling, but then there are genuinely good people trying to do good. Tom White (the former Texas Ranger who cracked the case) is one of them, and so is (Osage) Molly Burkhart. Molly is a woman whose opinions are devalued and her family is being murdered, but she doesn’t move away.

Tom took the cases seriously at a time of great corruption and prejudice. Both Molly and Tom are transitional figures, and part of the book is about the transformation into a modern country. Molly grew up in a lodge and, in a span of 30 years, she’s living in a mansion, married to a white man and with servants. Tom grew up in the Wild West, and by the time of the Osage murder cases he’s trying to use fingerprints and ballistic and handwriting analyses — and file paperwork, which he can’t stand.

Q: Have you been to Columbus before?

A: I have ... and I’m looking forward to coming back. I did a (2012) story for The New Yorker about a guy who lived in Columbus — William Morgan — who got caught up (in 1957) in the Cuban Revolution. (He joined Fidel Castro’s rebellion against Cuban President Fulgencio Batista) and was executed.

Q: You’ll be speaking in a series presented by the Thurber House, the boyhood home of a very famous “New Yorker” writer.

A: That’s a lovely connection, isn’t it? I love James Thurber.

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