Mary, Princess Royal and Princess of Orange (1631 - 1660). Mary, Princess Royal was Countess of Nassau by marriage to Prince William II, and co-regent for her son during his minority as Sovereign Prince of Orange from 1651 to 1660. She was the eldest daughter of King Charles I of England, Scotland, and Ireland and his wife, Henrietta Maria of France. Her only child, William succeeded her husband as Prince of Orange and later reigned as King of England, Ireland and Scotland. Mary was the first daughter of a British sovereign to hold the title Princess Royal. Scottish and English Royalty House of Stuart Charles I Children Prince Charles James, Duke of Cornwall and Rothesay Charles II Mary, Princess Royal and Princess of Orange James II & VII Princess Elizabeth Princess Anne Princess Catherine Prince Henry, Duke of Gloucester Henriette, Duchess of Orléans Grandchildren Prince Charles, Duke of Cambridge Prince James, Duke of Cambridge Prince Charles, Duke of Kendal Prince Edgar, Duke of Cambridge Princess Henrietta of York Princess Catherine of Yotk Princess Catherine Laura of York Princess Isabella of York Prince Charles, Duke of Cambridge Princess Elizabeth of York Princess Charlotte Maria of York v. t. e. Mary Henrietta was born at St. James's Palace, London to Charles I of England and Henrietta Maria, Queen of England and was named after her mother. Charles I designated her Princess Royal in 1642, thus establishing the tradition that the eldest daughter of the British sovereign might bear this title. The title came into being when Queen Henrietta Maria, the daughter of King Henry IV of France wished to imitate the way the eldest daughter of the French king was styled. Until that time, the eldest daughters of English and Scottish kings were variously titled lady or princess. Her father, Charles I, wished that Mary marry her first cousin Balthasar Charles, Prince of Asturias, the son of Philip IV of Spain, while her first cousin, Charles I Louis, Elector Palatine, was also a suitor for her hand. Both proposals fell through and she was betrothed to William, the son and heir of Frederick Henry, Prince of Orange and Stadtholder of the United Provinces, and of Amalia of Solms-Braunfels. The marriage took place on 2 May 1641 at the Chapel Royal, Whitehall Palace, London. The marriage was reputedly not consummated for several years because the bride was nine years old. In 1642, Mary moved to the Dutch Republic with her mother, Queen Henrietta Maria, and in 1644, as the daughter-in-law of the stadtholder, Frederick Henry, she became more engaged in courtly and public events. In March 1647, Mary's husband, William II, succeeded his father as stadholder. However, in November 1650, just after his attempt to capture Amsterdam from his political opponents, he died of smallpox. The couple's only child, Willem, was born a few days later. Mary, now a Dowager, was obliged to share the guardianship of her infant son with her mother-in-law, Amalia of Solms-Braunfels, and brother-in-law, Frederick William I, Elector of Brandenburg. They had more power over the young Prince's affairs than she, as evidenced by his being christened Willem, and not Charles as she had desired. She was unpopular with the Dutch because of her sympathies with her own family, the Stuarts. She lived in the palace of the Stadthouder at the Binnenhof in the Hague, the building complex that now houses the Senate of the Netherlands. Her boudoir is still intact. At length, public opinion having been further angered by the hospitality that she showed to her brothers, the exiled Charles II and the Duke of York, she was forbidden to receive her relatives. Her moral reputation was damaged by rumours that she was having an affair with Henry Jermyn, a member of her brother James' household. The rumours were probably untrue, but Charles II took them seriously, and tried to prevent any further contact between Jermyn and Mary. From 1654 to 1657, Mary was usually not in Holland. In 1657, she became regent on behalf of her son for the principality of Orange, but the difficulties of her position led her to implore the assistance of her first cousin Louis XIV of France. The restoration of Charles II in England and Scotland greatly enhanced the position of the Princess of Orange and her son in Holland. In September 1660, she returned to England. She died of smallpox on 24 December 1660, at Whitehall Palace, London and was buried in Westminster Abbey.