stadtholder of the Dutch provinces of Friesland, Groningen and Drenthe and an outstanding military leader during the Dutch Revolt, aka the Eighty Years War. He served under his cousins Maurice (1567-1625) and Frederick Henry (1584-1647) of Nassau, Princes of Orange.
He became a field marshal in 1607 and was second in command of the Dutch army. He was killed at the siege of Roermond while inspecting the trenches.
Portrait of Ernst Casimir, count of Nassau-Dietz
Workshop of Michiel Jansz. van Mierevelt (1567-1641)