Siegfried IV was the last Count of Northeim-Boyneburg and Homburg.Große Baudenkmäler Heft 338 Kloster Amelungsborn, Verlag DONAU Druck 5. Auflage 1998, p. 2 He gave the land at Amelungsborn for the foundation (in the 12th century) of the future Amelungsborn Abbey, a Cistercian monastery, which was officially settled by a community of monks from Altenkamp Abbey.
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