The miniature in the secret compartment is based on a painting of Gabrielle d'Estrées and her sister the Duchesse de Villars by an artist of the Fontainebleau School, circa 1595, now in the Louvre. The ladies' hairstyles have been fashioned for the late eighteenth century, whereas the king's attire is typical of the period of the original painting.
Gabrielle d'Estrées became Henry IV's mistress in 1591. She was already married to M. de Liancourt but after four years her marriage to him was annulled and Henry gave her the title of Marquise de Monceaux. Together they had three children. Henry, too, was married when their affair began but in 1599 he was granted permission by Pope Clement VIII to divorce Marguerite de Valois. The couple were due to marry in the same year, but Gabrielle suffered an attack of eclampsia and died giving birth to a stillborn child on 10 April. She was given a state funeral and her coffin was transported through a procession of princes, princesses and noblemen.