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.
Eighty Years' War (1566–1609) The first half of the Eighty Years' War between the Spanish Empire and the Dutch Republic was fought between 1566 and 1609. When the Twelve Years' Truce was signed in 1609, ending this stage of the war, the northern Netherlands had achieved "de facto" independence.