William IV (Willem Karel Hendrik Friso; 1 September 1711 – 22 October 1751) was Prince of Orange from birth and the first hereditary stadtholder of all the United Provinces of the Netherlands from 1747 until his death in 1751.

On 25 March 1734 he married at St James's Palace Anne, Princess Royal, eldest daughter of King George II of Great Britain and Caroline of Ansbach.

The conflict pitted Austria against France over the issue of whether Maria Theresa had the right to inherit her father Emperor Charles VI's crown.

The Dutch Republic sided with Austria in 1747 in order to maintain a buffer zone between itself and France, whereupon French troops invaded the Austrian Netherlands.

Nevertheless, he was also a Director-General of the Dutch East India Company, and his alliance with the business class deepened while the disparity between rich and poor grew.