Willem IV, Count van den Bergh (1537-1586) was the Dutch Stadtholder of Guelders and Zutphen from 1581 until his arrest for treason in 1583.

Here he became acquainted with his contemporary William the Silent, Prince of Orange, and married his eldest sister, Maria of Nassau, on 11 November 1556 at Moers.

In 1566 Willem was a prominent member of the League of Nobles (also known as the Compromis) that presented a petition of grievances about the suppression of heresy to the Brussels government of the new Regent Margaret of Parma (who acted for her brother Philip II of Spain).

[2] This prominence put him at odds with Fernando Álvarez de Toledo, 3rd Duke of Alba, who succeeded Margaret as governor-general of the Netherlands in 1567.

Willem was initially successful, and quickly conquered Doetinchem, Zutphen, Deventer, Zwolle, Kampen, and Steenwijk.

This ambition was initially thwarted when his other brother-in-law Johann VI, Count of Nassau-Dillenburg got the post on 10 March 1578.

In September 1583 the sudden seizure of Zutphen by the Spanish side cast suspicion on the stadtholder of Guelders.

[6] Willem was released after he promised to retire to his castle in Ulft and to remain neutral in the conflict.