Nielsen Hayden genealogy
Albrecht I

1. Albrecht I was born in 1236 (son of Otto I of Brunswick-Lüneburg and Matilde von Brandenburg); died on 15 Aug 1279. Notes:
"The Great." Duke of Brunswick.
Albrecht married Alessina de Monferrato on 1 Nov 1266. Alessina (daughter of Boniface II and Margereta of Savoy) died on 5 Feb 1285. [Group Sheet] [Family Chart]
Children:- Heinrich I of Brunswick was born in Aug 1267; died on 7 Sep 1322.
- Albrecht II of Brunswick was born about 1268; died on 22 Sep 1318; was buried in Brunswick Cathedral, Braunschweig, Lower Saxony, Germany.
- Matilde was born in 1276; died before 31 Aug 1318.
2. Otto I of Brunswick-Lüneburg was born in 1204 (son of Wilhelm of Brunswick-Lüneburg and Helene of Denmark); died on 19 Jun 1252. Notes:
"The Child." Duke of Brunswick-Lüneburg.
Otto married Matilde von Brandenburg. Matilde (daughter of Albrecht II of Brandenburg and Mathilde von Nieder-Lausitz) was born about 1210; died on 10 Jun 1261. [Group Sheet] [Family Chart]
3. Matilde von Brandenburg was born about 1210 (daughter of Albrecht II of Brandenburg and Mathilde von Nieder-Lausitz); died on 10 Jun 1261. Children:
- Adelheid of Brunswick-Lüneburg died on 12 Jun 1274.
- Agnes of Brunswick-Lüneburg died on 18 Mar 1302.
- Helene of Brunswick-Lüneburg was born on 18 Mar 1223; died on 6 Sep 1273.
- 1. Albrecht I was born in 1236; died on 15 Aug 1279.
Generation: 3
4. Wilhelm of Brunswick-Lüneburg was born on 11 Apr 1184 in Winchester, Hampshire, England (son of Heinrich of Saxony and Matilda of England); died on 13 Dec 1213 in Lüneburg, Lower Saxony, Germany. Notes:
Called "Longsword." Duke of Brunswick-Lüneburg. Also called William of Winchester.
Wilhelm married Helene of Denmark in Jul 1202 in Hamburg, Germany. Helene (daughter of Valdemar I den Store, King of Denmark and Sofie of Polotsk) was born about 1180; died on 22 Nov 1233. [Group Sheet] [Family Chart]
5. Helene of Denmark was born about 1180 (daughter of Valdemar I den Store, King of Denmark and Sofie of Polotsk); died on 22 Nov 1233. Children:
- 2. Otto I of Brunswick-Lüneburg was born in 1204; died on 19 Jun 1252.
6. Albrecht II of Brandenburg was born about 1177 (son of Otto I of Brandenburg and Adelheid); died on 25 Feb 1220. Notes:
Margrave of Brandenburg.
Albrecht married Mathilde von Nieder-Lausitz in Aug 1205. Mathilde (daughter of Konrad von Nieder-Lausitz and Elisabeth of Poland) died in 1255. [Group Sheet] [Family Chart]
7. Mathilde von Nieder-Lausitz (daughter of Konrad von Nieder-Lausitz and Elisabeth of Poland); died in 1255. Notes:
Markgräfin von der Nieder-Lausitz.
Children:
- 3. Matilde von Brandenburg was born about 1210; died on 10 Jun 1261.
- Johann I of Brandenburg was born in 1213; died on 4 Apr 1266.
- Otto III of Brandenburg was born about 1215; died on 9 Oct 1267.
Generation: 4
8. Heinrich of Saxony was born in 1129 (son of Heinrich of Saxony and Gertrud von Süpplinburg); died on 6 Aug 1195 in Braunschweig, Lower Saxony, Germany. Notes:
"The Lion." Duke of Saxony and Bavaria.
Heinrich married Matilda of England on 1 Feb 1168. Matilda (daughter of Henry II, King of England and Eleanor of Aquitaine, Queen Consort of France; Queen Consort of England) was born in 1156 in London, England; died on 28 Jun 1189. [Group Sheet] [Family Chart]
9. Matilda of England was born in 1156 in London, England (daughter of Henry II, King of England and Eleanor of Aquitaine, Queen Consort of France; Queen Consort of England); died on 28 Jun 1189. Children:
- Heinrich I of Rhein was born about 1173; died on 28 Apr 1227.
- 4. Wilhelm of Brunswick-Lüneburg was born on 11 Apr 1184 in Winchester, Hampshire, England; died on 13 Dec 1213 in Lüneburg, Lower Saxony, Germany.
10. Valdemar I den Store, King of Denmark was born on 14 Jan 1131 (son of St. Canute Lavard and Ingeborg of Kiev); died on 12 May 1182 in Vordingborg, Denmark. Valdemar married Sofie of Polotsk in 1157. Sofie (daughter of Wolodar Glebowitsch and Richiza of Poland) was born about 1140; died on 5 May 1198. [Group Sheet] [Family Chart]
11. Sofie of Polotsk was born about 1140 (daughter of Wolodar Glebowitsch and Richiza of Poland); died on 5 May 1198. Children:
- Richiza of Denmark died on 8 May 1220; was buried in Ringsted, Zealand, Denmark.
- Sophie Valdemarsdatter of Denmark was born in 1159; died in 1208.
- Valdemar II Sejr, King of Denmark was born on 28 Jun 1170; died on 28 Mar 1241.
- 5. Helene of Denmark was born about 1180; died on 22 Nov 1233.
12. Otto I of Brandenburg was born about 21 Jun 1126 (son of Albrecht of Saxony and Sophia von Winzenburg); died on 7 Mar 1184. Notes:
Margrave of Brandenburg.
Otto married Adelheid. [Group Sheet] [Family Chart]
13. Adelheid Notes:
Also called Ada of Holland.
Children:
- 6. Albrecht II of Brandenburg was born about 1177; died on 25 Feb 1220.
14. Konrad von Nieder-Lausitz was born about 1156 (son of Dedo V von Nieder-Lausitz and Matilde von Heinsberg); died on 6 May 1210. Notes:
Margrave of Nieder-Lausitz.
Konrad married Elisabeth of Poland after 29 Jan 1180. Elisabeth (daughter of Mieszko III, High Duke of Poland and Elisabeth of Hungary) died on 2 Apr 1209. [Group Sheet] [Family Chart]
15. Elisabeth of Poland (daughter of Mieszko III, High Duke of Poland and Elisabeth of Hungary); died on 2 Apr 1209. Children:
- 7. Mathilde von Nieder-Lausitz died in 1255.