|House of Brabant|
Maison de Brabant
House of Hainaut, House of Louvain
|Ducal noble family|
|Country|| Holy Roman Empire|
Kingdom of France
Kingdom of England
Duchy of Brabant
|Etymology||Descendant of Reginar|
|Founder||Reginar I, Count of Hainaut|
|Current head||Direct line extinct|
|Final ruler||Joanna, Duchess of Brabant|
The Reginarids (or Regnarids, Regniers, Reiniers, etc.) or House of Reginar were a family of magnates in Lower Lotharingia during the Carolingian and Ottonian period. Their modern name is derived from the personal name which many members of the family bore, and which is seen as a Leitname of the family. At least two Dukes of Lotharingia in the 10th century belonged to this family. After a period of exile and rebellion, the two brothers who returned to power founded the first dynasties of the County of Hainault and County of Louvain. The latter were ancestors of the House of Brabant, Landgraves and later Dukes of Brabant, Lothier and Limburg. The Reginarid Brabant dynasty ended in 1355, leaving its duchies to the House of Luxembourg which in turn left them to the House of Valois-Burgundy in 1383. Junior branches of the male line include the medieval male line of the English House of Percy, Earls of Northumberland, and the German House of Hesse which ruled Hesse from 1264 until 1918 and still exists today.
The first probable ancestor known with any confidence is Gilbert, Count of the Maasgau (mentioned in 841) who served King Lothair I, but defected to Lothair's half-brother Charles the Bald during the civil war of 840–843. In 846 Gilbert abducted an unnamed daughter of Lothair and married her in an attempt to force Lothair to reinstate him. Reginar, Duke of Lorraine (c. 850–916) is believed to be Gilbert's son. Following the death of Charles the Fat, the Reginarids began a long fight with the Conradines for supremacy in Lotharingia. When they triumphed, in 910, it was in electing Charles the Simple as king. It was the combined forces of Bruno I of Lorraine and the Carolingians of West Francia that finally broke the Reginarids' hold on power. In 958, Reginar III had his lands confiscated and redistributed to Gerard, Count of Metz, of the Matfridings, enemies of his family since the reign of Zwentibold.
The Reginarids were no longer a unified family by the end of the tenth century. Their descendants in Mons and Louvain continued their spirit of opposition to the king. The house also produced a queen-consort of England in the form of Adeliza of Leuven, who married Henry I of England.