 Its historic and strategic importance dates back to its founding as a Roman era fortress site and Frankish count's castle site in the Early Middle Ages.It was an important bastion along the Spanish road when Spain was the principal European power influencing the whole western hemisphere and beyond in the 14th–17th centuries.Luxembourg is a founding member of the European Union, NATO, the United Nations, Benelux, and the Western European Union, reflecting the political consensus in favour of economic, political, and military integration.