1. A country of northwest Europe bordering on Belgium, Germany, and France. Created as a duchy in 1354, it was ruled successively by Burgundy, Spain, Austria, and France between 1443 and 1797, and it was made a grand duchy of the Netherlands by the Congress of Vienna (1814-1815). In 1839 the greater part of it passed to Belgium. The remainder became autonomous in 1848 and was declared a neutral and independent territory in 1867. Luxembourg is the capital.
2. also Luxembourg City The capital of Luxembourg, in the southern part of the country. It developed around a heavily fortified tenth-century castle.