Dr. Harry Howard Holmes or H.H. Holmes is known to be America's first serial killers. He constructed a ¨Murder Castle¨ in which he lived in and killed in. The three story building was constructed to perfectly fit his needs of killing. In his early life he was a medical student at the University of Michigan where he stole corpses and used them to make bogus insurance claims. In the 1893 world's fair he opened up his home to visitors and unfortunately most did not make it out. He was first charged with fraud and during his trial he confessed to killing 27 people. But it's estimated that there are about 100 victims. He lost his trial and was later hanged.
Lavinia Fisher 1793-1820
Lavinia Fisher was operating before Holmes but is not known to be the first serial killer even though she was alive before Holmes was even born. She is known to be the first woman serial killer. She owned a hostel with her husband the travelers, mostly men, would go to their rooms with tea that Fisher had poisoned then her husband would go up to the room and stab the men to make sure they were dead. She was later arrested and hung. Her number of victims are unknown.