Madame Delphine MacCarthy Lalaurie was a wealthy New Orleans socialite and notorious enslaver. In 1832, Madame Lalaurie moved into a neoclassical mansion at the intersection of today’s Royal and Governor Nicholls Streets with her third husband Dr. Leonard Louis Nicolas Lalaurie. Madame Lalaurie hosted many lavish parties there. However, through the years, information surfaced about her mistreatment of enslaved people.
According to historian Carolyn Marrow Long, Madame Lalaurie was first investigated in 1828 for cruelty towards enslaved people. Though court records related to this investigation have not been found, there is documentation that Madame Lalaurie paid for legal services and sold a number of enslaved people following the investigation. 
On April 10, 1834, a fire broke out in the Lalaurie mansion. A group of onlookers gathered outside of the home as it burned. According to The New Orleans Bee, the city’s French-language newspaper, firefighters discovered “seven slaves, more or less horribly mutilated” locked inside the building as they attempted to control the flames.  The Bee went on to condemn the “barbarous and fiendish atrocities committed by the woman Lalaurie upon the persons of her slaves.”  The firefighters brought these enslaved people to the Cabildo.
As word of Lalauries’ misdeeds surfaced, neighbors became enraged. According to The Bee, a crowd of 4,000 people gathered at the Cabildo.  Neighbors ransacked the mansion and destroyed what was left of the burned mansion. The Lalauries fled to Lake Pontchartrain and ultimately relocated to Paris. Madame Lalaurie died in Paris, but it is believed her body was brought back to New Orleans and buried at the St. Louis Cemetery. 
Today, many tourists visit the Lalaurie Mansion because it is supposedly haunted. Historian Tiya Miles has criticized the manner in which tourism and pop-culture have glorified the mistreatment of enslaved people through ghost stories used to entertain visitors. 
The structure that stands at 1140 Royal Street today was constructed in 1838 as a private residence and later used as a school and apartments.