public profile
Son of Heinrich III 'the Fat' Duke of Saxony-Werra & Margrave of Friesland & Count of Northeim and Gertrud von Braunschweig Brother of Otto II III von Northeim, Graf; Gertrude von Northeim von Lotharingia Countess Palatine & Heiress of Friesland and Richenza von Northeim Half brother of Dietrich III, Count of Katlenburg