Louis Cesar de La Baume Le Blanc, duc de Vaujours, duc de La Valliere (9 October 1708 – 16 November 1780) was a French nobleman, bibliophile and military man. The present duc d'Uzes and duc de Luynes descend from him.
Louis Cesar was the son of Charles Francois de La Baume Le Blanc, marquis and then duc de La Valliere, and his wife, Marie Therese de Noailles, a daughter of Anne Jules de Noailles, duc de Noailles.
His father was a nephew of Louise de La Valliere, the first official mistress of King Louis XIV of France. On his father's side of the family, Louis Cesar's relatives at court included Louise de La Valliere's daughter by Louis XIV, Marie Anne de Bourbon, princesse de Conti. On his mother's side, his aunt was Marie Victoire de Noailles, the wife of Louis Alexandre de Bourbon, comte de Toulouse, and mother of Louis Jean Marie de Bourbon, duc de Penthievre, the wealthiest man in France during Louis Cesar's lifetime. His uncle, Adrien Maurice de Noailles married Francoise Charlotte d'Aubigne, the niece of Madame de Maintenon. Another cousin was Louis de Pardaillan de Gondrin, duc d'Antin, a great-grandson of Madame de Montespan.
When Louise de La Valliere left Versailles for a religious life after her displacement in the king's affections by Madame de Montespan, she gave the duchies of Vaujours and La Valliere to her daughter, the princesse de Conti. The princess sold them in 1698 to Louis Cesar's father. From his birth, Louis Cesar was known at court as the marquis de La Valliere. His father retained the Vaujours title for himself until his own death in 1739.
In 1727 at the early age of nineteen, Louis Cesar was promoted to the rank of colonel of the regiment under the title of duc de La Valliere. In 1730, his father also gave him the duchy of Vaujours. With this new title came the rank of pair de France. Even though his father officially gave up the duchy in 1732, he was still styled at court as the duc de Vaujours.
In 1732 Louis Cesar married Jeanne Julie Francoise de Crussol d'Uzes, the daughter of Charles Emmanuel de Crussol (1743–1815) and his wife Emilie de La Rochefoucauld. His wife was a member of the House of Crussol, the most important peers in France after that of the Princes of the Blood.
Upon his father's death in 1739, Louis Cesar became the new duc de La Valliere and was made the governor of Bourbonnais. In addition, he inherited the Chateau de Champs-sur-Marne. Around 1750, he added a beautiful rococo salon chinois (Chinese salon) to the chateau with wall paintings by noted artist Christophe Huet. The property had been given to his father by his cousin, the princesse de Conti, in 1718 in order to settle some debts. At the chateau, Louis Cesar entertained many of the famous writers of the day, including Diderot, Voltaire, d'Alembert and Francois-Augustin de Paradis de Moncrif, with whom he also corresponded regularly.
Monsieur de La Valliere was also created the Captain of the Hunt by Louis XV of France as well as the Grand Falconer of France in 1748. King Louis XV respected him, and Louis Cesar became close with the king's mistress, the famous Madame de Pompadour, who named him the master of her private theatre. In 1749 the king bestowed upon him the Order of the Holy Spirit in a ceremony which took place at the Palace of Versailles on 25 May. The order was the most prestigious in France.
After the construction of a magnificent new chateau at Montrouge around 1750, the duke gradually abandoned the Chateau de Champs-sur-Marne. Eventually, he tried to sell the estate, but he could not find a buyer and was forced to rent it out. Between July 1757 and January 1759, he leased the estate to Madame de Pompadour for 12,000 livres per year. The marquise spent 200,000 livres in less than eighteen months to renovate the chateau. In November 1757, she received the prince de Soubise there after his defeat at the Battle of Rossbach. As the king did not like the chateau, the marquise left it at the beginning of 1759. In 1763, the duke finally sold Champs to Gabriel Michel de Tharon (1702–1765), a rich shipowner.
Louis Cesar was one of the greatest bibliophiles of his time. With the assistance of his librarian, the abbe Rive, he bought entire libraries and sold whatever he already had. His great library was eventually sold in three stages, first in 1767; then in 1783 and again in 1788. Part of the famous collection was acquired by the comte d'Artois, brother of Louis XVI and future king of France. That part of the library was incorporated into the Bibliotheque de l'Arsenal in Paris.
The duke's library was famous:
The duke also wrote two books: Ballets, opera, et autres ouvrages lyriques (1760) and the Bibliotheque du Theatre-Francais (1768, 3 vol. in-12). The latter was edited by Barthelemy Mercier de Saint-Leger.
Louis Cesar and his wife, Jeanne Julie Francoise de Crussol d'Uzes, had only one child, a daughter. As the duchy of La Valliere had previously been held by several women, including Louise de La Valliere and her daughter, the princesse de Conti, his daughter was able to inherit the title. On her death, however, the title became extinct.Adrienne Emilie Felicite de La Baume Le Blanc (29 September 1740 - ? duchesse de Chatillon et de La Valliere, dame de Wideville married 4 April 1756 to Louis Gaucher, duc de Chatillon, and had issue.
9 October 1708 - 1730: The Marquis of La Valliere (Monsieur le marquis de La Valliere)
1730 - 22 August 1739: The Duke of Vaujours (Monsieur le duc de Vaujours)
22 August 1739 - 16 November 1780: The Duke of La Valliere (Monsieur le duc de La Valliere)