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.
Dutch States Army The Dutch States Army (Dutch: "Staatse leger" ) was the army of the Dutch Republic. It was usually called this, because it was formally the army of the States-General of the Netherlands, the sovereign power of that federal republic. This mercenary army was brought to such a size and state of readiness that it was able to hold its own against the armies of the major European powers of the extended 17th century, Habsburg Spain and the France of Louis XIV, despite the fact that these powers possessed far larger military resources than the Republic. It played a major role in the Eighty Years' War (opposite the Spanish Army of Flanders) and in the wars of the Grand Alliance with France after 1672.