The 1893 Chicago World's Fair was an amazing celebration of the American gilded age. It was an exposition of firsts. First movie theater, first Ferris Wheel, first Pabst Blue Ribbon, and America's first serial killer.
H.H. was born Herman Mudgett, a moniker he abandoned for obvious reasons. His terrible name aside, Herman did not have a happy childhood. When he wasn't getting violently beaten by his alcoholic father, he was getting tortured and bullied by his future alcoholic classmates. Herman dealt with his problems by dissecting small animals. I think we can all see where this one is going. He attended university to become a medical doctor, an endeavor he paid for by using cadavers from the university in complicated life insurance schemes. This did not sit well with his first wife for some reason, so she left, a fact that didn't bother Herman in the least. He soon got remarried, without ever getting officially divorced, and started traveling the country, taking on odd jobs and murdering a few children here and there. Herman's new wife was apparently the most oblivious woman in history.
After a few years of random murder, Herman, finding himself in Chicago, decided to shift homicides from a hobby to a full on industry. He secured a city block on which he built a massive edifice that was supposedly a hotel, but would later be called the Murder Castle. The Murder Castle was built over several years with no workman allowed to be part of its construction for more than a few weeks at a time. It was a maze of hallways and false doors. Air tight and sound proof rooms provided the perfect spots for various types of murder. Strangulation, asphyxiation, poison, and starvation just to name a few. In the basement Herman set up his own personal laboratory where he dissected and did away with the bodies using acid, lime, and incineration. The entire monstrosity was funded by a combination of life insurance scams and the selling of skeletons across the country to doctors’ offices and universities.
Herman's second wife must have been the most oblivious woman in history. Not only did he run a murder factory right under her nose, he also fueled it by seducing women from across the country, luring them into his lair. Woman after woman fell to the charms of Herman. Several of these mistresses stayed in his hotel for months before being dealt with. Herman even got married for a third time, even though he was still legally married to his first two wives, though in the grand scheme of things, his penchant for bigamy probably wasn't that big of a deal what with the wanton murder and all. Herman's "business" reached its high point during the Chicago World's Fair. With thousands of people flocking to the city, many couldn't be that picky when it came to available hotel rooms.
Soon after the end of the World's Fair, Herman was forced to flee to avoid the police. His second wife probably just thought he was leaving for cigarettes or something. Herman tried to stay low, but couldn't keep himself from running a few non-murdery horse swindles and life insurance scams. Growing bored, Herman killed his only friend, kidnapped three of the man's children, and then led his widow on what he thought was probably a merry chase across the U.S. and Canada. This chase of course ended with the children getting murdered, because at this point how else could it end. Herman was soon captured, tried for several of his murders, and hanged. It's estimated that he killed up to 200 people. His last words basically hinted that he was probably the devil.
Image: https://commons.wikimedia.org/wiki/File:H._H._Holmes.jpg