In 1685 Louis XIV created in Saint-Cyr a college for the filles pauvres de la noblesse (poor noble girls) at the request of madame de Maintenon (Isabelle Huppert), his long-term mistress and latterly his unacknowledged wife. It’s probable that madame de Maintenon’s request was a response to her own upbringing in straitened circumstances. In 1715 on the death of Louis XIV she retired to Saint-Cyr where she died in 1719.
However, at least in the movie, the best intentions have unintended consequences. It needs to be listened to in French to catch the gradual change in the speech of girls from regional dialects to ‘proper’ French.
Annick Legout, Thi Thanh Tu Nguyen and Laurence Couture were credited for makeup.