Mary, Princess Royal and Princess of Orange

Names
	Mary Henrietta Stuart

Mary
Mary
Princess Royal
	Portrait by Adriaen Hanneman, 1660
Princess consort of Orange; Countess consort of Nassau;
Tenure	14 March 1647 – 6 November 1650
Born	4 November 1631; St James's Palace, City of Westminster, Middlesex, Kingdom of England
Died	24 December 1660 (aged 29); Whitehall Palace, City of Westminster, Middlesex, Kingdom of England
Burial	29 December 1660; Westminster Abbey, City of Westminster
Spouse	William II, Prince of Orange (m. 1641; died 1650)
Issue	William III
Names
Names
	Mary Henrietta Stuart
House	Stuart
Father	Charles I of England
Mother	Henrietta Maria of France

Mary, Princess Royal (Mary Henrietta Stuart; 4 November 1631 – 24 December 1660), was a British princess, a member of the House of Stuart, and by marriage Princess of Orange and Countess of Nassau. She acted as regent for her minor son from 1651 to 1660. She was the first holder of the title Princess Royal.

The eldest daughter of King Charles I of England and Queen Henrietta Maria, Mary was married to the future stadtholder of the Netherlands, William II of Orange, at nine years old in 1641. Initially, she remained in England with her parents because of the heated political situation in England until early 1642, when she and her mother left for the Netherlands. Five years later in 1647, Mary's husband inherited the titles of Prince of Orange and Stadtholder of Holland, Zeeland, Utrecht, Guelders, Overijssel and Groningen in the United Provinces of the Netherlands.

Eight days after her husband's death in 1650, Mary gave birth to a son, William III of Orange, who later became King of England, Scotland and Ireland. Mary, who became the only guardian of her son, was not popular in the Netherlands because of her support of her brothers and her difficult relationship with her mother-in-law Amalia of Solms-Braunfels, who considered the princess young and inexperienced. After the restoration of the monarchy in England in 1660, Mary departed for celebrations in London, where she fell ill with smallpox and died.