Marie Casimire and her sister were the only surviving children of Henri de la Grange d'Arquien, a French nobleman. She came to Poland at the age of five years as a lady in waiting to Marie Louise Gonzaga, the French-born Queen of Poland from 1645 to 1672, wife and consort to two Polish kings — Władysław IV Vasa and later his brother John II Casimir Vasa. At the court she met John Sobieski, who arrived there in 1656, but she was first married to Jan "Sobiepan" Zamoyski in 1658, with whom she had four children, all died in infancy. Zamoyski died in 1665 and the widowed Marie Casimire eventually married Sobieski on the 14 July the same year. The couple had thirteen children together, but only four of them survived until adult age — Jakub, Aleksander, Konstanty and Teresa. John Sobieski was electedKing of Poland in 1674, not without the influence of his wife. As the Queen of Poland, Marie Casimire quickly became unpopular, as she supported the proposed Polish–French alliance, while at the same time striving to gain privileges for her family from the French king Louis XIV. The Royal couple became famous for their love letters, most of which were written from 1665 to 1683, when they were parted either due to John III Sobieski's military engagements or her travels to Paris. The letters give insight not only into the authentic feelings of the loving couple, but also their reflections on contemporary issues and difficulties, as well as down-to-earth matters concerning the royal household and little day-to-day decisions made by the monarch, who often consulted his wife about them. Published long after the death of both of them, they can be credited with popularizing the King's way of addressing the Queen by the very diminutive form of her first name — "Marysieńka". She is widely remembered and referred to in Poland that way. Marie Casimire was a hard, arrogant, self-centered woman. With all their love, the king and the queen quarreled, and after the king's death, their son hurried to send his mother to a distinguished exile in Rome, where she was expected to be accepted with the same respect and prestige as Christina, Queen of Sweden, a well-known art patron and founder of the Academy of Arcadia. But Marie Casimire did not enjoy Queen Christina's virtues, neither her nobility, her intelligence, nor her intellect. She believed that her devoted support of Catholicism vis-a-vis the Turks would receive an enthusiastic reception from the church in Rome, but that the Swedish queen, who had converted from Protestantism to Catholicism, had also elevated her status in the eyes of the Vatican. Nevertheless, Marie Casimire was well received and became a music patron who was mainly patronized by Domenico Scarlatti. In his role as maestro di Capella, he composed and produced seven operas with her, as a continuation of the operas written by his father, Alessandro. Marysieńka spent the last one and a half years of her life in France, where in January 1716 she died after rinsing the stomach administered by a doctor. The coffin was moved to the chapel of St. Eustace in the church of St. Savior in Blois. On the other hand, the heart was put in a casket in the local Jesuit church. Then in 1717, the coffin with Marysieńka's body was buried in the Capuchin church in Warsaw, next to John III. In 1733, both bodies were transported to the Wawel Cathedral in Krakow.
Issue
Marie Casimire first married Jan "Sobiepan" Zamoyski on March 3, 1658 in Warsaw. They had four children, all of whom died in infancy:
Ludwika Maria.
Son.
Katarzyna Barbara.
Daughter.
Zamoyski himself died April 2, 1665. Marie Casimire remarried in July of that year to the future Jan III Sobieski. This marriage was famously happy and the couple had thirteen children, though many did not survive to adulthood:
