Frederick Henry's Meuse campaign

[1][2][3] In 1572, 6 years after the revolt broke out, the Geuzen who backed the Prince of Orange, captured a lot of cities in the Netherlands.

Shortly after, Philip II sent the Duke of Parma to the Netherlands as governor and reconquered large parts of the Netherlands previously occupied and captured by the Rebels, including the cities that were captured during the Meuse campaign, the most notable one being Parma's siege of Maastricht.

Ernest arrived at Roermond on the 2nd of June, a few hours later he was inspecting their respective trenches when he got hit with a bullet, killing him.

After Venlo was captured, Frederick Henry heard about his death and arrived at Roermond with his entire army on the 4th of June.

[7] Even though the campaign was a success for the Dutch, the cities of Venlo and Roermond would be recaptured by Spanish forces under Cardinal-Infante Ferdinand during his counter-offensive in the summer of 1637.

The military situation of the Eighty Years' War in 1629
The death of Ernest Casimir during the siege of Roermond
This illustration shows Frederick Henry in front of the besieged city of Maastricht