John I, Duke of Saxony

John I Johann I. von Sachsen, Engern und Westfalen (de)
officially: Duke of Saxony, Angria and Westphalia colloquially: Duke of Saxe-Lauenburg
Coat-of-arms of John I
Duchy of Saxony (joint rule with his younger brother Albert II)
Joint Reign	1260–1282
Predecessor	Albert I, Duke of Saxony
Successors	Albert II with John I's sons Eric I, John II and Albert III (joint rule)
Born	1249
Died	30 July 1285 Wittenberg upon Elbe
Saxon consort	Ingeborg Birgersdotter of Småland
Issue Detail	Helen (*ca. 1272–1337*) Elisabeth (*ca. 1274–1306*) Eric I John II Albert III Sophia (*?–1319*)
House of	Ascania (by birth)
Father	Albert I, Duke of Saxony
Mother	Helen of Brunswick and Lunenburg
Religion	Roman Catholic

Duke John I of Saxony (1249 – 30 July 1285, Wittenberg upon Elbe) was the elder son of Duke Albert I of Saxony and his third wife Helen of Brunswick and Lunenburg, a daughter of Otto the Child. John and his younger brother Albert II jointly ruled the Duchy of Saxony after the death of their father Albert I in 1260.

Life

In 1269, 1272 and 1282 the brothers gradually divided their governing competences within the three territorially unconnected Saxon areas (one called Land of Hadeln around Otterndorf, another around Lauenburg upon Elbe and the third around Wittenberg), thus preparing a partition. As part of this arrangement John I became Burgrave of Magdeburg in 1269.

In the imperial election in 1273 Albert II represented the jointly ruling brothers. John I resigned in 1282 in favour of his three minor sons Eric I, John II and Albert III. Later John I entered the Franciscan monastery in Wittenberg, becoming its warden (guardian), which position he held until he died. John I's sons and their uncle Albert II continued the joint rule in Saxony, with the sons entering into the government on growing major. The last document, mentioning Albert II with his nephews as Saxon fellow dukes dates back to 1295.^[1]

Marriage and issue

In 1270 John married Ingeborg Birgersdotter of Småland (*ca. 1253–30 June 1302*, Mölln), a daughter or grandchild of Birger jarl. They had eight children, among them the following:

• Helen (*ca. 1272–1337*), married with (1) Count Günther IX of Schwarzburg-Blankenburg (*?–1289*), (2) in ca. 1297 Adolph VI, Count of Holstein-Schauenburg
• Elisabeth (*ca. 1274– before 1306*), married in 1287 with Valdemar IV, Duke of Schleswig.
• John II (*ca. 1275–22 April 1321*)
• Eric I (*1280/1282–1359/1361*)
• Albert III (*ca. 1281–October 1308*)
• Sophia (*?–13 December 1319*), prioress in Plötzkau

Ancestors

Ancestors of John I, Duke of Saxony

16. Otto, Count of Ballenstedt               8. Albert the Bear                       17. Eilika of Saxony               4. Bernard III, Duke of Saxony                             18. Herman I, Count of Winzenburg               9. Sophie of Winzenburg                       19. a countess of Everstein               2. Albert I, Duke of Saxony                                   20. Magnus I of Sweden               10. Canute V of Denmark                       21. Richeza of Poland               5. Birgitte of Denmark                             1. John I, Duke of Saxony                                         24. Henry the Lion               12. William of Winchester, Lord of Lüneburg                       25. Matilda of England               6. Otto I, Duke of Brunswick-Lüneburg                             26. Valdemar I of Denmark               13. Helena of Denmark                       27. Sophia of Minsk               3. Helene of Brunswick-Lüneburg                                   28. Otto I, Margrave of Brandenburg               14. Albert II, Margrave of Brandenburg                       29. Ada of Holland               7. Matilda of Brandenburg, Duchess of Brunswick-Lüneburg                             30. Conrad II, Margrave of Lusatia               15. Matilda of Lusatia                       31. Elisabeth of Greater Poland

Notes

1. Cordula Bornefeld, "Die Herzöge von Sachsen-Lauenburg", in: Die Fürsten des Landes: Herzöge und Grafen von Schleswig, Holstein und Lauenburg [De slevigske hertuger; German], Carsten Porskrog Rasmussen (ed.) on behalf of the Gesellschaft für Schleswig-Holsteinische Geschichte, Neumünster: Wachholtz, 2008, pp. 373-389, here p. 375. ISBN 978-3-529-02606-5