Nielsen Hayden genealogy
Descendants of Berta de Clavesena
Father: Boniface del Vasto
Berta de Clavesena
Guillermo VIII-VI ( - 17 Sep 1225 Halmyros, Greece)(m. Bef 9 Aug 1202)
   └─ Boniface II (Abt 1202 - Between 12 Jun 1253 and 10 Dec 1256)
    Margereta of Savoy ( - 1254)(m. 9 Dec 1235)
       └─ Alessina de Monferrato ( - 5 Feb 1285)
        Albrecht I (1236 - 15 Aug 1279)(m. 1 Nov 1266)
           ├─ Heinrich I of Brunswick (Aug 1267 - 7 Sep 1322) =>
           │ + Agnes von Meissen (Bef 1264 - Aft 1 Feb 1332)(m. 1282)
           ├─ Albrecht II of Brunswick (Abt 1268 -
           │ 22 Sep 1318 bur.Brunswick Cathedral, Braunschweig, Lower Saxony, Germany) =>
           │ 22 Sep 1318 bur.Brunswick Cathedral, Braunschweig, Lower Saxony, Germany) =>
           │ + Richza of Werle ( - Aft 2 Oct 1312 bur.Göttingen, Lower Saxony, Germany)(m. 10 Jan 1284)
            + Henryk I-III von Schliesen (Between 1251 and 1260 - 9 Dec 1309)(m. Bef Apr 1290)