Diana Of Poitiers, duchess of Valentinois, mistress of Henry II. of France, born Sept. 3, 1499, died at Anet, in Orleanais, April 22, 1566. At the age of 13 she became the wife of Louis de Breze, count de Maulevrier, and grand seneschal of Normandy, by whom she had two daughters. She was attached to the court of Queen Claude, and when her father, the seigneur de St. Vallier, had been condemned to death for favoring the escape of the constable de Bourbon, she so touched the heart of Francis I. by her tears and beauty, that the punishment was commuted. In 1531 her husband died, and Diana, putting on widow's weeds, expressed a resolve to wear them till her death; but this did not prevent her when nearly 40 years old from becoming the mistress of the dauphin (her junior by nearly 20 years), afterward Henry II. The duchess d'Etampes then possessed the affections of Francis I., and the two favorites divided the court until the accession of the dauphin in 1547, when Diana became almost mistress of the kingdom, and her rival was sent into exile. The beauty and accomplishments of the young queen, Catharine de' Medici, could not prevail against her influence.
The king delighted in giving public tokens of his infatuation, admitted her to his councils, and in 1548 created her duchess of Valenti-nois. She retained her ascendancy until Henry's death in 1559, when she retired to the palace built for her by her royal lover at Anet; but in 1561 she was recalled by Catharine de' Medici to exert her influence in detaching the constable de Montmorency from the Chatillons. From that time until her death she remained in retirement. Her power over the king, even when she had reached the age of 60, was due no less to her beauty than to her intellect. She spent large sums in charity.