In 1568 his brother William the Silent took up arms against Philip II of Spain and Adolf fought beside him in Brabant.
Adolf then joined the force under his brother Louis of Nassau in the north, where he died at the Battle of Heiligerlee after his horse bolted and crossed Spanish lines.
[1][2] The Spanish troops at Heiligerlee were commanded by Jan van Ligne, duke of Arenberg (or Aremberg), who also died in the battle.
The death of Adolf of Nassau is mentioned in the Dutch national anthem (4th verse): There are several accounts about his burial:
Originally, Van Mierop wanted the monument to be placed on a stone hill but, after some disagreement, Geefs designed an octagonal pedestal.