Eugene Butler was born around 1849 in Royalton, New York. In 1882, he moved to the Dakota Territory and established a 480-acre farm near Niagara, North Dakota. Butler lived a reclusive life, never marrying and rarely interacting with neighbors. He hired farmhands during the summer months but was known for his eccentric behavior and paranoia.​

By the early 1900s, Butler's mental health deteriorated. He experienced hallucinations and believed invisible people were pursuing him. In 1906, his erratic behavior led to his commitment to the North Dakota State Hospital in Jamestown. Despite his delusions, he showed no violent tendencies during his confinement. Butler died in the asylum on October 22, 1913.

In June 1915, two years after Butler's death, workers renovating his former farmhouse discovered six human skeletons buried beneath the floorboards. The victims, all male and aged between 15 and 18, had suffered crushing blows to the skull. Some had broken legs, likely to fit them into shallow graves.

Authorities believed the victims were transient farmhands employed by Butler between 1900 and 1906. It's suspected that Butler, driven by paranoia, murdered them fearing they intended to rob him. The victims' identities remain unknown, and the case files have been lost over time.

The discovery shocked the community, and Butler posthumously earned the nicknames "The Great Plains Butcher" and "The Midnight Rider." Despite efforts, the victims have never been identified, and the full extent of Butler's crimes remains a mystery.