He was the son of John William Friso of the Frisian branch of the house of Orange-Nassau and a descendant of the brother of William the Silent. After the death of his father, he became at age seven chief executive and military commander of the province of Friesland.
In an effort to quell internal strife amongst the various factions, in 1747 the States-General selected William IV as their leader, making it a hereditary position. At first, he was popular with the people when he spoke out against the power and wealth of the Dutch business establishment. Nevertheless, he was Director-General of the Dutch East India Company and his alliance with the business class deepened while the disparity between rich and poor grew. He served as stadtholder of all the Netherlands until his death in 1751.
William of Orange, the son of William II, Prince of Orange and Mary Stuart, was born in The Hague.
William III felt insecure about his position; though only his wife was formally eligible to assume the throne, he wished to reign as King in his own right, rather than as a mere consort.
William was opposed to the imposition of such constraints, but he wisely chose not to engage in a conflict with Parliament and agreed to abide by the statute.