Gabrielle d'Estrées, French mistress of Henry IV of France (b. 1571)

Gabrielle d'Estrées, Duchess of Beaufort and Verneuil, Marchioness of Monceaux (French: [ɡabʁijɛl dɛstʁe]; 1573 – 10 April 1599) was a mistress, confidante and adviser of Henry IV of France. She persuaded Henry to renounce Protestantism in favour of Catholicism in 1593. Later she urged French Catholics to accept the Edict of Nantes, which granted certain rights to the Protestants. Being legally impossible for the King to marry her as he was already married to Margaret of Valois, he controversially filed for an annulment to Pope Clement VIII in February 1599 to end his childless first marriage, and announced his intention to marry Gabrielle and have her crowned the next Queen of France, while legitimizing their three children that were born out of wedlock. Her coronation and wedding never occurred due to her untimely and sudden death.