Louise Julie, Comtesse de Mailly
Louise Julie de Mailly-Nesle, comtesse de Mailly (1710–1751) was the eldest of the five famous de Nesle sisters, four of whom would become the mistress of King Louis XV of France.
Louise Julie was born the eldest daughter of Louis de Mailly, marquis de Nesle et de Mailly, Prince d'Orange (1689 - 1767), and his wife, Armande Félice de La Porte Mazarin (1691 - 1729). Her parents had been married in 1709. Her mother was the daughter of Paul Jules de La Porte, duc Mazarin et de La Meilleraye (1666 - 1731), the son of the famous adventuress, Hortense Mancini, the niece of Cardinal Mazarin. Louise Julie had four younger full sisters:
The only one of the de Nesle sisters not to become one of Louis XV's mistresses was the marquise de Flavacourt. Louise Julie was the first sister to attract the king, but it was Marie Anne who was the most successful in manipulating him and becoming politically powerful.
Louise Julie also had a younger half-sister, Henriette de Bourbon (1725 - 1780), Mademoiselle de Verneuil, from her mother's relationship with the duc de Bourbon, the chief minister of Louis XV from 1723 to 1726.
In her youth, Louise Julie was known as Mademoiselle de Mailly. On 31 May 1726, she married her cousin, Louis Alexandre de Mailly, comte de Mailly (born 1694). Her husband died on 30 July 1743.
In 1729, upon the death of her mother, Louise Julie replaced her as dame du palais or lady-in-waiting to the queen.
At this point in time, Louis XV, who suffered from restlessness and needed to be entertained, something the queen was unable to do, became more inclined to listen when queen Marie was unfavorable compared to other women, and Cardinal Fleury, who wished to prevent Marie from eventually getting any influence over the king, favored the idea of the king taking a mistress as long as she was apolitical.
In 1732, Louise Julie caught the attention of King Louis XV, and became his mistress with the approval of her spouse. Although she became the king's mistress in 1732, Madame de Mailly was not officially recognized as his maîtresse en titre until 1738. During these years, the relationship was not official, and she was known at court as the Fair Unknown. Queen Marie unsuccessfully tried to find out who the mistress was, and did display her displeasure over the state of affairs, but the adultery had the support of Cardinal Fleury, because de Mailly was not interested in politics, and after the first years of the king's adultery, Marie resigned to it. In 1737, the relationship between the king and queen discontinued as the queen ended their sexual relations after her last childbirth, and after this, Louise Julie de Mailly was officially recognized at court as the mistress of the king.
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