Edward Bates Soper was born on February 7, 1855, in Kearney, Missouri. He was the second of eight children in his family. His parents were farmers named John Lewis Soper and Sarah Hyatt Soper. Not much is known about his early life. However, it is recorded that at the age of 20, he stole a horse and sold it in Kansas City. 

Over time, he developed a deep-seated resentment toward his father, John. The reasons for this hatred are not clear. On January 30, 1880, Soper plotted to kill his father. He started a literary society and invited his father to attend. When his father arrived, Soper hid and shot him four times, killing him. After the murder, he disposed of the gun in a creek and acted as if nothing had happened.

Following the murder of his father, Soper was arrested for horse theft and served two years in a local penitentiary. Upon his release, he married Ardela Hunt, a woman who was 35 years old and had two children from a previous marriage. Their marriage seemed happy at first. However, they began to argue when Ardela decided to join a Christian church, which Soper opposed.

On January 30, 1880, Edward Soper shot his father, John Soper, four times in a feeding lot, killing him. He then hid the gun in a nearby creek and returned to a literary society, pretending nothing had happened. Another man, Thomas Maib, was wrongfully convicted of the murder based on circumstantial evidence.

In 1891, after serving a two-year sentence for horse theft, Soper married Ardela Hunt, who had two children from a previous marriage. The family lived on a farm in Archie, Missouri. On April 21, 1891, Soper killed Ardela and her two children, Maude, aged 6, and Gillis, aged 3, with an axe while they slept. After the murders, he wrote letters claiming he could not take care of them. He then locked the doors of the home and left town. Three days later, neighbors found the decomposing bodies inside the house. An arrest warrant was issued for Soper, who had fled.

Later, in June 1891, a body found in the Missouri River was initially believed to be Soper, but it was later misidentified. In truth, Soper had escaped to Albina, Oregon, using the name R. S. "Sandy" Soper. He remarried and had a son named Gilis. On April 16, 1897, Soper took his 2-year-old son to a bank of the Willamette River and drowned him. He buried the boy’s body nearby.

Soper remained on the run for a month, using another alias, "Homer Lee." His arrest came when Officer Sam E. Lowe recognized his name in a newspaper and tracked him down. During transport back to Missouri, Soper confessed to killing his wife and children but initially denied killing his father. After being questioned, he showed the authorities where he had buried his son.

Soper was extradited back to Missouri, where he was charged with his wife’s murder. He pleaded insanity but was eventually convicted and sentenced to death. His appeal to the Supreme Court of Missouri was rejected. On March 30, 1899, he was hanged in Harrisonville, Missouri, in front of a small crowd. Before his execution, he ate a hearty meal and refused religious counseling, saying as his final words, "All is done." An autopsy showed that his neck was broken when he fell.