Counts of Louvain

The likely ancestor of the Reginars, Gilbert, Count of the Maasgau, a vassal of the West Frankish king Charles the Bald, married a daughter of the Carolingian emperor Lothair I in 846.

His son and successor Gilbert swore fealty to the East Frankish king Henry the Fowler in 925 and three years later married his daughter Gerberga of Saxony.

In 1013, Lambert annexed part of the county of Bruningrode, located between Louvain and Tienen, and this became a source of long-running conflict with the prince-bishops of Liège.

Lambert's family gained great influence in the Holy Roman Empire, acquiring more comital titles over time.

His son Lambert II is also mentioned as a count of Brussels, where he had the St. Michael's Church erected to house the relics of Saint Gudula.