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?
Adolf van Nieuwenaar Adolf van Nieuwenaar, Count of Limburg and Moers (also: Adolf von Neuenahr) (c. 1545 – 18 October 1589) was a statesman and soldier, who was stadtholder of Overijssel, Guelders and Utrecht for the States-General of the Netherlands during the Eighty Years' War.
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.