[1] His death marked the beginning of the First Stadtholderless Period, leading to the rise of Johan De Witt, who stayed in power for the next 22 years.

His son William also became Stadtholder of the Five Dutch Provinces in 1672, marking the end of the formentioned Stadtholderless Period.

In January 1640, William of Orange proposed to Mary, Princess Royal, the eldest daughter of Charles I of England, Scotland, & Ireland, by his wife Queen Henrietta Maria of France.

A prerequisite for such a union was Mary's conversion to Catholicism, but the princess, who at the request of her mother studied the basics of the Catholic religion, did not want to change her faith.

On 10 February 1641, Charles announced to Parliament that the betrothal of his daughter was actually concluded and that it only remained to consider this union from a political point of view.

[a] Mary and William were congratulated by courtiers, and received several gifts; in addition, in honour of the couple, a volley of 120 guns was fired.

In 1647, his father, Frederick Henry died on 14 March,[2] after a long illness (he suffered from gout and possibly some kind of Alzheimer's in the last few years of his life), and William II succeeded to both his hereditary titles and his elective offices as stadtholder of six of the seven provinces: Holland, Zeeland, Utrecht, Guelders, Overijssel and Groningen at the young age of 21.

Under Frederick Henry, the Netherlands had largely won the war, and since 1646 had been negotiating with Spain on the terms for ending it.

William imprisoned eight members of the States of Holland (including Jacob de Witt) in the castle of Loevestein.

[7] On 2 May 1641, William II married Mary, Princess Royal, second surviving child and eldest daughter of King Charles I of England by his French consort Henrietta Maria of France.