Marie Casimire Louise de la Grange d'Arquien

Marie Casimire Louise de la Grange d'Arquien, in Polish: Maria Kazimiera, known also by the diminutive form "Marysieńka" (June 28, 1641, Nevers – January 1, 1716, Blois) was the Queen of Poland, consort to King Jan III Sobieski, from 1674 to 1696.

She came to Poland at the age of 5 years as a lady in waiting to Ludwika Maria Gonzaga, the Queen of Poland from 1645 to 1672, wife and consort to two Polish kings — Władysław IV Waza and later his brother (who succeeded him) Jan Kazimierz. At the court she met Jan Sobieski, who arrived there in 1656, but she was first married to Jan "Sobiepan" Zamoyski in 1658. Zamoyski, however, died in 1665 and the widowed Maria Kazimiera 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 (who later became Kurfürstin of Bavaria and mother to Emperor Karl VII).

Jan Sobieski was elected King of Poland in 1672, not without the influence of his wife. As the Queen of Poland, Maria Kazimiera supported the proposed Polish–French alliance, while at the same time striving to gain privileges for her family from the French king Louis XIV.

Maria Kazimiera Sobieska

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 Jan 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.