As money at that time seemed more important than royal blood, an agreement was soon reached and in April 1641 the fifteen-year-old Prince of Orange arrived to claim his nine-year-old bride. They married in London on the 2nd of May and, at the end of the month, the Prince returned alone to The Netherlands. However, because of political expediency, early in 1642, Mary, together with her mother,departed for The Netherlands. On arrival they were greeted by the young Prince of Orange and Elizabeth of Bohemia, aunt of the bride. After a short while Mary was iven her own apartments where she was instructed in the Dutch language and customs. As no dowry had been arranged as yet, her father-in-law, Frederik Hendrik, soon found he had a much more expensive daughter-in-law than he had bargained for. Soon Mary was unhappy, believing she was spied upon, her governess, Lady Roxburgh, was replaced by Lady Stanhope.
Her mother-in-law, Amalia, had been so eager to obtain a royal princess for her son, but took an instant dislike to the young Mary. At the same time Mary looked down on her mother-in-law, as she had been a mere lady-in-waiting to her aunt Elizabeth when she was
Electress Palatine and, for so short a period, Queen of Bohemia. Mary's mother, Queen Henrietta Maria, stayed much longer than the Dutch expected, spending her time raising money and support for her husband in England where civil war was now inevitable. In 1647 her father-in-law died and her husband became Stadhouder of Holland. Then in 1649 she lost her father, King Charles I, when he was beheaded by the Parliamentarians. Early in 1650 Mary became pregnant while her husband was busy in matters of state. In fact he
was embroiled in arguments with the city of Amsterdam, yet still found time to go hunting and staying away all night in all kinds of weather. One day he became so ill that he had to be transported to The Hague by ship. Soon it became obvious that he suffered from smallpox and he died on 6 November 1650, while eight days later Mary gave birth to
their son.
At first there were arguments about the baby's name. Mary wanted 'Charles', but her mother-in-law had to insist that the name of a Prince of Orange had to be Willem. More arguments were to follow because of her mother-in-law trying to strengthen the position of the House of Orange, while Mary was interested only in the affairs of her brother, Charles II. In 1653 the Parliamentarians allowed Mary's thirteen-year-old brother, Henry, Duke of Gloucester, to leave England and join her in The Netherlands. Mary became very fond of her brother, after a while she had to let him go to join their mother in Paris. In February 1656 Mary herself went to France to meet her mother for the first time in twelve years. She had then been a child but was now she a beautiful woman. A marvellous reception awaited her and she was in no hurry to return to Holland, especially as she entertained the hopes that her cousin, the young French king, Louis XIV, might want to marry her. However, these hopes came to nothing.
In 1660 her brother, Charles II, was restored on the throne of England and she went to London for the celebrations. However, the family reunion was marred by the untimely death, on 13 September 1660, of her brother Henry, who died of smallpox. Only after Henry's death did their mother arrive, and the once beautiful queen was now regarded as "a very little plain old woman". Nevertheless festivities were held as Christmas approached but, after several late nights, Mary became ill and, although for five days, she was bled unceasingly, on 24 December 1660, she too, succumbed to smallpox.
 

Source: Leo van de Pas