Marie Delphine Macarty was born on March 19, 1787, into a prominent Creole family in Spanish-controlled New Orleans. Her lineage included Irish-French heritage, with her grandfather having emigrated from Ireland in the early 18th century. Delphine’s family was politically and socially powerful; her cousin Augustin de Macarty later served as mayor of New Orleans, and her uncle Esteban Rodríguez Miró had been the Spanish colonial governor of Louisiana and Florida.

Delphine grew up during a volatile time in the Atlantic world. The Haitian Revolution, which began in 1791 when she was four years old, and the subsequent slave revolts in Louisiana, such as the Pointe Coupée conspiracy (1795) and the German Coast uprising (1811), deeply shaped the psychology of white slaveholders. These events stoked widespread fear and reinforced brutal attitudes toward enslaved people among Louisiana elites, including the Macarty family.

Delphine married three times. Her first husband, Don Ramón de Lopez y Angulo, was a Spanish official whom she married at just 13 years old. He died in 1804 while en route to Spain. Delphine gave birth to their only child, a daughter named Borquita, shortly after his death.

In 1808, she married Jean Blanque, a wealthy lawyer and politician. They had four children and lived at a property later known as Villa Blanque. Blanque died in 1816, leaving Delphine a widow once again.

Her third and final marriage occurred in 1825, when she wed Dr. Leonard Louis Nicolas LaLaurie, a physician 15 years her junior. The relationship was strained, and in 1832 Delphine filed for legal separation due to cruelty—though it appears the separation was never finalized. She managed her own property independently, purchasing a lot on 1140 Royal Street in 1831 and commissioning the construction of a grand mansion with slave quarters. This residence would become infamous.

Despite the social expectations of the time, Delphine remained a highly influential figure in New Orleans society. She hosted events, mingled with the elite, and was widely regarded as charming and poised. 

The horrific abuses attributed to Madame LaLaurie came to light on April 10, 1834, when a fire broke out at her Royal Street mansion. The blaze originated in the kitchen and was later revealed to have been set deliberately by an enslaved cook, chained to the stove, who reportedly started the fire in a desperate attempt to expose the cruelty within the house. As local authorities and citizens responded to the fire, they uncovered something far more disturbing than structural damage.

Inside the attic of the mansion, they discovered a torture chamber. Bound slaves were found in various states of mutilation and starvation. Eyewitness reports and early journalistic accounts described individuals who had been beaten, flayed, or subjected to grotesque medical experimentation. Some accounts claimed that bodies were found with limbs stretched, mouths sewn shut, or even organs exposed while the victims were still alive. Although some of these accounts were exaggerated over time or influenced by sensationalism, the core facts remained: LaLaurie had inflicted prolonged, deliberate torture on the enslaved people under her control.

Witnesses stated that the victims were "singularly haggard and wretched," even by the already grim standards of slavery. The enslaved people had suffered years of abuse that was concealed behind the facade of aristocratic elegance. The truth had long circulated in whispers, but no action had been taken until the fire forced the horrors into public view.

An enraged mob of New Orleans citizens descended on the mansion after the discovery, destroying furniture, tearing down walls, and ransacking the house. By then, however, Delphine LaLaurie had already escaped. With the help of her social connections, she fled Louisiana via the Lake Pontchartrain route and eventually made her way to Paris, France.

Despite public outcry and widespread revulsion, LaLaurie was never arrested, charged, or extradited. For years, her whereabouts were uncertain, although she was confirmed to be living in France as late as the 1840s. She died in Paris on December 7, 1849. Some legends claim she returned to New Orleans in secret, but no verifiable record supports this theory.

The exact number of victims tortured and/or murdered by LaLaurie is unknown. At least several enslaved individuals died as a result of her actions, while others were permanently maimed. Because she was never tried in court, she was never officially labeled a serial killer or murderer by the justice system, but historical consensus acknowledges her culpability in some of the worst documented atrocities committed against enslaved people in American history.