The de Grandpré mansion was a stately, three-storey villa owned by the French merchant Philippe de Grandpré during the eighteenth century. Located in New Orleans, the mansion functioned as the residence of Philippe, his family and his servants.
In 1776, Philippe passed away, causing ownership of the mansion to pass to his wife, Madeleine de L'Isle. Later, in 1777, a confrontation ensued at the villa between Aveline, Philippe's daughter and secretly an Assassin, and Madeleine, after the former had found out about the latter's position as Master Templar.
Built on an incline, the mansion stood atop a raised foundation, with twin staircases leading up to the front door, which gave the building an imposing air. It also possessed a walkway underneath that directly led to the sizeable backyard. There, a pigeon coop stood, from which Aveline occasionally retrieved messages sent by Gérald Blanc.
Inside, the ground floor was composed of a large dining room, where a harpsichord stood, and a staircase that led to the first floor. There were also two doors, barring the front door, one of which led to the balcony at the back of the mansion, while the other connected to the slaves' quarters. The first floor contained a few rooms, among which was Philippe and Madeleine's bedroom, while the second floor had only Aveline's bedroom.
- When entering the mansion, Aveline's outfit would automatically switch to that of the lady. When leaving the house, her guise was determined by the exit she chose; the front door was used for the lady outfit, a side door for the slave outfit and the window in Aveline's bedroom for the Assassin outfit.
- Given that Aveline was unable to legally inherit the mansion, it is unknown what happened to it after Madeleine's death in 1777.