Killers of the Flower Moon: The Osage Murders and the Birth of the FBI by David Grann

For four years, in the 1920's, the richest people per capita in the world were the members of the Osage Nation in Oklahoma. They lived in mansions on their oil-rich land. 

Then they are being killed. Mollie Burkhart watched her family die, one by one. They were shot, poisoned, blown up. 

Other Osage natives were being killed and white people were inheriting their headrights. Each tribe member had a guardian, who had the right to handle any money that the tribe member could spend.
While the trials that took place say that this rampage lasted 4 years, there were numerous deaths that were never attributed for. There are probably about 300 deaths that were manipulated to inherit these fortunes. 

This was a very disturbing part of our history. 

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