Upon the invasion of Germanic Franks from the East during the Migration Period in the 5th century, the Luxembourg region became part of Francia and the Carolingian Empire.

Since 925, it has belonged to East Francia, predecessor of the Kingdom of Germany and the Holy Roman Empire, and large parts were held by the Abbey of Echternach.

From the Early Middle Ages to the Renaissance, authors attributed different names to Luxembourg, such as: Lucilinburhuc, Lutzburg, Lützelburg, Luccelemburc, Lichtburg.

[2] The ruined, supposedly Roman, fortification called Lucilinburhuc was first mentioned in 963, when Count Siegfried acquired it from Wikerus, Abbot of St. Maximin's Abbey in Trier.

He was possibly a son of Gilbert, Duke of Lorraine, and his mother Cunigunda was a granddaughter of the West Frankish King Louis the Stammerer.

The castle dominated a stretch of the old Roman road linking Reims, Arlon and Trier that provided prospects for trade and taxation.

In addition to the small town near the Bockfiels and the Roman road, a further settlement was established in the Alzette Valley, today the Grund quarter of Luxembourg.

When Henry the Blind died in 1196, Count Otto I of Burgundy (a son of the Hohenstaufen emperor Frederick Barbarossa) raised claims to the throne.

Henry the Blind's daughter, Ermesinde, married Count Theobald I of Bar, thus securing her own succession as Countess of Luxembourg.