Alexandre Dumas 
Louise de la Valliere 

Louise de La Valliere (Francoise Louise de La Baume Le Blanc; 6 August 1644 – 7 June 1710) was a mistress of Louis XIV of France from 1661 to 1667. She later became the Duchess of La Valliere and Duchess of Vaujours in her own right. Unlike her rival, Madame de Montespan, she has no known surviving descendants. Louise was also very religious and she led a religious penance for herself near the end of her life. (Excerpt from Wikipedia)