Mme. Marie Delphine LaLaurie was a well-to-do socialite in 19th century New Orleans. In 1832, she and her husband, the doctor Leonard Louis LaLaurie, built a mansion at 1140 Royal Street that became the talk of the town for years to come. For two years, Mme. LaLaurie held extraordinary parties in the house with the entire first floor used as a ballroom. She was a kind and gracious host, and as lovely as anyone could wish, but there was a dark and twisted side to her that remained hidden for quite some time.
There were rumors that LaLaurie was abusive to her servants. At one time, she was seen driving a little servant girl off of the roof with a bullwhip; the little girl fell to her death, and witnesses said that she was buried in the well in the front lawn. That was just a rumor, though, and nobody could prove that anything had happened. In April of 1834, however, the full scope of her atrocities would come to light. A servant started a fire in the kitchen during a dinner party, and soon the whole neighborhood was out to help the Madame save her belongings. After a while, someone noticed that none of the servants were helping. The rumor quickly spread through the crowd that the servants were locked up in the attic, roasting alive. A few brave souls broke down the door and discovered horrors beyond belief. Men were shackled to the floor, hanging by the neck, locked in cages with holes in their skulls and sores full of worms. Some had limbs amputated; others had broken joints set in unnatural positions. Apparently, LaLaurie had been carrying out some kind of sick medical experiments on her servants. The entire town was shocked and horrified.
It didn't take long for their horror to turn into indignation and anger. A mob formed outside of the LaLaurie mansion and people cried out for blood and vengeance. All at once, the LaLaurie carriage burst forth from the carriage house, carrying the Doctor and his wife quickly through the mob and out of town. Nobody ever found out what happened to the two of them. Some reported that they moved to northern Louisiana; others say that they ended up in Paris. Some would say, however, that the Madame never made a clean break.
At the turn of the century, the LaLaurie house was turned into apartments, and soon the rumors of haunting began. People saw black men dragging chains up and down the stairs, only to disappear. One black tenant awoke in the middle of the night to find a ghastly white woman strangling him; just when he thought he'd run out of breath, two phantom black hands came out of the darkness and dragged her away, kicking and screaming. Screams and moans consistently come from the attic, where few dare to venture, and the screams of Mme. LaLaurie's condemned soul have also been heard. Attempts have been made to clear her name. One of her descendants maintains that her abusive actions were in retaliation against the black servant who had molested one of her daughters. The events themselves are arguable as well: there is disagreement over how many slaves were in the attic, what condition they were in, and what happened to the LaLauries after they fled New Orleans. "Say what you will," the locals say, though, "la maison est hantezse."
Sources: Hauck, Dennis William. Haunted Places: The National Directory.
"Haunted History: Haunted New Orleans," The History Channel.