Nicolas Mius, Governor of Marseille, worked for Louise de Coligny’s father Admiral Gaspard II de Coligny as an interpreter. On August 25, 1572, Nicolas Mius was a victim of the St. Bartholomew’s Day Massacre. On this day the Admiral told those with him “to save yourselves.” Everyone left Admiral Gaspard II de Coligny except Nicolas Mius, who stayed by the Admiral's side and was murdered with him. Following the Admiral's death, his wife Countess Jacqueline de Montbel took Nicolas Mius’ children under her wing and adopted his son whom she sent to her Mother to raise in her care along with her daughter, Beatrice. Jacqueline then put Nicolas' daughters, Charlotte Mius d’Entremont and Louise Mius d’Entremont, into the care of her stepdaughter, Louise de Coligny, Princess of Orange, who raised them. Countess Jacqueline signed documents to which all Nicolas Mius’ descendants, whether male or female, would carry the name and coat of arms of Jacqueline's father, Count d’Entremont.
Louise then married William the Silent on 24 April 1583. She became the mother of Frederick Henry in 1584, William's fourth legitimate son and future prince of Orange. It is said that she warned her husband about Balthasar Gérard, because she thought him sinister. Catholic Gérard murdered William in July 1584 in Delft.
