Background
In 1228 she married Otto I, Duke of Brunswick-Lüneburg, a son of William of Winchester.
Duke of Brunswick Margrave of Brandenburg
In 1228 she married Otto I, Duke of Brunswick-Lüneburg, a son of William of Winchester.
She died on 10 June 1261 in Lüneburg. Mathilde and Otto had the following known children:
Elizabeth (died 1266), married William II of Holland
Helen (died 1273), married Albert I, Duke of Saxony and Hermann II, Landgrave of Thuringia
Adelaide (died 1274), married Henry I, Landgrave of Hesse
Matilda (died around 1295), married Henry II, Prince of Anhalt-Aschersleben
Agnes, married Wizlaw II, Duke of Rügeneral
Albert (died 1279)
John (died 1277)
Otto, Bishop of Hildesheim (died 1279)
Conrad, Prince-Bishop of Verden (died 1300).
