There are tons of really weird things that have happened in history. Most of them are really, really hard to believe. One of those is that four sisters all became mistresses of the same king, Louis XV. They were the de Mailly-Nesle sisters, and before you ask, this story isn’t made up.
Louise Julie de Mailly-Nesle, the eldest of the five de Mailly-Nesle sisters, was born in 1710. Her mother was Armande Félice de La Porte Mazarin, and if that name sounds familiar, Armande’s grandmother was Hortense Mancini. Armande was a lady-in-waiting to the queen, Marie Leszczyńska. Louise had four sisters: Pauline Félicité, Diane Adélaïde, Hortense Félicité, and Marie Anne. Armande also had an affair with Louis Henri, the Duke of Bourbon, and had a daughter, Henriette de Bourbon, with him. Louise’s father, Louis de Mailly, wasn’t that faithful to his wife either.
An interesting fact about Armande: she actually challenged another woman to a duel. Armande was the Duke of Richelieu’s lover, but he was also having an affair with the Vicomtesse de Polignac. Armande challenged the Vicomtesse to a duel, and Armande ended up being injured in her shoulder. The Duke of Richelieu didn’t want to choose between them, so Armande just moved on to her next lover, the Duke of Bourbon.
Louise was married off to her cousin in 1726, the not at all very important Louis Alexandre de Mailly, the Comte de Mailly. She didn’t want to marry him and was forced into it by her family. She was only sixteen, and he was thirty-two. Don’t even remember his name: all that matters is that Louise got married. Also, she was known as Madame de Mailly, which is kind of nice, since she didn’t have to tweak Mademoiselle de Mailly-Nesle so much.
Louise’s mother died in 1729. At that point, Armande had become Dame du Palais to Queen Marie, and Louise inherited her mother’s role. She also had to help arrange entertainment for the very restless king. Eventually, Louise actually fell in love with King Louis XV. And there was someone totally fine with her becoming one of Louis’s first mistresses.
So, at this point, a guy named Cardinal Fleury was ruling France pretty much on his own, and the king wasn’t doing anything about it. Fleury was afraid that if the queen wasn’t out of the way and if the king still liked her and spent time with her, then she would have influence over the king and Fleury would no longer be the de facto ruler of France. Louise didn’t seem to be interested in politics, so she’d make the perfect mistress for King Louis.
Louise had to tell her husband about this whole thing, and surprisingly but also not so surprisingly, Louise’s husband was totally fine with Louise and the king having an affair since that would certainly mean that he would end up with maybe some more money and power, so their affair started around 1732. Louise was very beautiful and would also have been very entertaining to speak to, but there was one little thing that could’ve been better: Louise was a very clumsy woman, nowhere near the definition of “graceful”.
The queen suffered a miscarriage and stopped sleeping with her husband after that, so everything was going Cardinal Fleury’s (and also Louise’s) way. Louise Julie and also Cardinal Fleury wanted to keep the affair thing private, so they did. But there were obviously rumors going around that the king had taken a mistress. People called her The Fair Unknown because Cardinal Fleury really did well keeping this a secret.

It didn’t take long for the queen to hear about this, and she was livid. After all, as far as she knew, King Louis had been faithful to her for their whole marriage until this point, so she was not okay with Louis having a mistress. Queen Marie was obsessed with finding out who The Fair Unknown was, but because Cardinal Fleury was amazing at secrecy stuff, she just had to give up.
Louise would’ve had a lot of influence over the king, so eventually, it wasn’t just the queen who wanted to know who The Fair Unknown was, everyone really wanted to find out. The queen no longer had much influence over King Louis after her miscarriage, so if the courtiers could find out who the king’s mistress was, they could become friends with her, and then they would be very powerful people.
Louise would sneak into the king’s rooms at night wearing a hood, and in 1738, Gabriel Bicheher came up with an ingenious plan to find out who The Fair Unknown was. He would go up to Louise Julie while she was sneaking into the king’s rooms and he would knock her hood off. Complicated, I know. I wonder why it took people six years to think of that.
The plan was successful, and after a day or so, the whole court knew exactly who the king’s mistress was: his wife’s lady-in-waiting. King Louis wasn’t ready to get rid of her just yet, so he had dinner with her. These 18th-century schemes are so interesting. Basically, he was having just a regular dinner, and then Louise Julie entered the room. She didn’t say anything, she just sat down next to him and they began eating their food. And just like that, Louise was a Maitresse-en-titre, the official mistress of King Louis XV.
Louise Julie was given rooms next to the king’s so she didn’t have to sneak into his rooms with her hood. This obviously hurt the queen, but Queen Marie didn’t think Louise was such a bad person to be around like Louis’s future mistresses, she was just hurt because Louise was King Louis’s first mistress.
Now that their relationship was public, King Louis and Louise Julie argued all the time. She was scared that he had another mistress, and because she was genuinely in love with Louis, their arguments about that never stopped. They were always arguing, even in front of other people.
Louise once received a letter from someone named Monsieur de Luc, asking her to use her influence on the king to help him do something, and Louise Julie—who was only King Louis’s mistress because she loved him—took it right to the king, who was livid that Louise had even received that letter, even though she had no intention of doing anything with it.
Louise Julie loved her sisters very much, so when her sister, Pauline Félicité, asked if Louise would invite her to court, Louise agreed without even thinking about it. She wanted to make her sisters happy, after all. Unfortunately, inviting Pauline to court was one of her first mistakes.
The moment Pauline set foot in Versailles, she started getting ideas. If she could replace Louise Julie as King Louis’s mistress, then she could get a good husband, some money, and everything she wanted. So, Pauline set her plan into action. Pauline didn’t even have to try, actually, because Louis fell in love with Pauline immediately.
Pauline became the king’s unofficial mistress. Louise still held the title of Maitresse-en-titre, and still had her rooms next to his as things had been for a while. Louise had the title, and Pauline took care of the duties that came with it. To make things a bit less complicated, King Louis had Pauline married off to the Marquis de Vintimille so that she could stay at court.
Louise Julie never had any children with King Louis, but Pauline became pregnant with Louis’s son soon after marrying the Marquis. Madame de Vintimille ended up dying in childbirth. Louise Julie and Pauline had been very close before the whole mistress thing, so Louise Julie was heartbroken.
Pauline’s remains were displayed so that people could mourn her. People never liked Pauline, so instead of mourning her, a mob came in and mutilated Pauline’s body. Being the king’s mistress isn’t always great. Louise was so devastated that her sister had died that she washed the feet of the poor, a Catholic rite.
Following Pauline’s death, Louise Julie’s youngest sister, Marie Anne, who had recently been widowed, asked her sister to invite her to court. Louise certainly hadn’t learned from her mistakes, so she went ahead and invited Marie Anne to court. Marie Anne was extremely beautiful, but she already had a lover she did not want to give up, so it must have seemed okay to Louise.
Louise, however, didn’t know that there were people that weren’t satisfied with her as royal mistress. They weren’t happy with Cardinal Fleury’s pacifist ways, so they wanted someone who could influence the king and get rid of Fleury. Louise had no interest in politics, and that’s why Fleury had chosen her as King Louis’s mistress in the first place, and that was why people started to try and get rid of Louise Julie.
At a masked ball, the Duke of Richelieu (not the one Louise’s mother, Armande, had had an affair with) introduced Marie Anne to King Louis. And King Louis XV fell in love with yet another one of the de Mailly-Nesle sisters. It’s also probably important to note that the third of the sisters, Diane Adélaïde, was an unofficial mistress of the king from about 1742 to 1745.

So, Marie Anne originally didn’t want to give up her current lover, but once she realized that the king was completely fine with giving up Louise Julie for Marie Anne, she also started trying to get rid of her sister. Cardinal Fleury, who really needed Louise Julie to stay in her position, tried to convince her that her sisters were literally plotting against her, but Louise just didn’t think that her sisters would do anything to hurt her, so she didn’t listen to him.
So, basically, one of the queen’s ladies was promoted, so there was a job opening there. Louise Julie had to get it to stay at court, as she had just been kicked out of her role as official mistress, but Marie Anne also wanted to stay, so the two sisters were literally fighting over a job working for the queen while both wanted to be her husband’s mistress.
Marie Anne convinced Louise Julie to give up her position for the fourth de Mailly-Nesle sister, Hortense Félicité, and Louise did. Hortense was the only one of the sisters who never became a royal mistress, so you might think that this was an okay choice for Louise Julie, until you realize that by resigning, Louise could no longer be at court.
She stayed there for a little while longer, though. Sometimes she would even eat dinner with the king, though he would only talk about how much he loved Marie Anne at their meals. King Louis asked her to leave once, but Louise broke down crying and asked Louis to allow her to stay for a little while longer. Louis agreed, but the furniture was moved out of her rooms next to the king’s because they were being readied for Marie Anne.
Marie Anne was livid that her sister wasn’t leaving, but eventually, Cardinal Fleury told her that maybe she should just leave for the sake of her dignity. Before she left, though, she wanted to have a last dinner with King Louis. She was sobbing at their dinner, and he said that he’d come to see her a few days after she left.
Louis never came, though, because of Marie Anne. Marie Anne didn’t want him to go and maybe feel sorry for Louise Julie and let her come back to court and eventually have her become his mistress again. So, the horrible little sister kept Louise waiting, until she eventually got fed up with it all and entered a convent. She became very religious and lived at the convent until her death in 1751 at the age of 41.
Marie Anne was at court for a very short time until she died in 1744. Diane Adélaïde died in 1769, and Hortense Félicité, the only one of the sisters who never became Louis XV’s mistress, lived long enough to be imprisoned during the French Revolution and died in 1799 at the age of 84. Maybe being a royal mistress isn’t that amazing after all.
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