Françoise de Montmorency-Fosseux

Françoise de Montmorency-Fosseux (French pronunciation: [fʁɑ̃swaz də mɔ̃mɔʁɑ̃si fosø] ⓘ; 1566 – 6 December 1614), also called "La Belle Fosseuse" or "La Fosseuse",[1] was mistress to King Henry III of Navarre (future King Henry IV of France) from 1579 to 1581.

She finally gave in to his advances during a voyage to Montauban, and afterwards grew ambitious and arrogant towards Queen Margaret, carrying on the affair in hopes of marriage.

[3] Margaret proposed banishing her rival from court, but La Fosseuse screamed that she would refuse to cooperate.

[4] The doctor informed Henry, and Margaret made sure the lying-in proceeded as discreetly as possible by acting as midwife.

[5] Henry took this as a personal insult, but did nothing to retaliate, as he had then fallen to the charms of "the beautiful Corisande," Diane d'Andoins.