What is the name of the historical county, later duchy of the Holy Roman Empire, located in the Low Countries that  Adolf van Nieuwenaar worked for in the  Eighty Years' War?
Guelders Guelders or Gueldres (Dutch: "Gelre" , German: "Geldern" ) is a historical county, later duchy of the Holy Roman Empire, located in the Low Countries.
Nassau-Usingen Nassau-Usingen was a county of the Holy Roman Empire in the Upper Rhenish Circle that became a principality in 1688.