Luxembourg an independent state under the personal possession of William I of the Netherlands with a Prussian garrison to guard the city against another invasion from France. In 1839, following the turmoil of the Belgian Revolution, the purely Oil-speaking part of Luxembourg was ceded to Belgium and the Luxembourgish-speaking part (except the Arelerland, the area around Arlon) became what is the present state of Luxembourg. Luxembourg is a founding member of the European Union, OECD, United Nations, NATO, and Benelux. The city of Luxembourg, which is the country's capital and largest city, is the seat of several institutions and agencies of
Netherlands They were probably the most commonly used names, besides Flanders, another pars pro toto for the Low Countries, especially in Romance language speaking Europe. The Eighty Years' War (1568–1648) divided the Low Countries into an independent northern Dutch Republic (or Latinised "Belgica Foederata", "Federated Netherlands", the precursor state of the Netherlands) and a Spanish controlled Southern Netherlands (Latinised "Belgica Regia", "Royal Netherlands", the precursor state of Belgium). The Low Countries today is a designation that includes the countries the Netherlands, Belgium and Luxembourg, although in most Romance languages, the term "Low Countries" is used as the name for the Netherlands