"Henry of Brunswick-Lüneburg (Latin Henricus, died 14 October 1416), Duke of Brunswick-Lüneburg, called Henry the Mild, was prince of Lüneburg from 1388 to 1409 jointly with his brother Bernard I, Duke of Brunswick-Lüneburg, from 1400 to 1409 also of Wolfenbüttel, and from 1409 until his death sole prince of Lüneburg.
Henry was the fourth son of Magnus with the Necklace, Duke of Brunswick-Lüneburg. He participated in the prosecution of the murderers of his brother Frederick, elected King of the Romans, after 1400. Henry ravaged the Eichsfeld, a possession of the archbishop of Mainz, who was suspected to be involved in the murder. Only in 1405, a peace was ratified between Brunswick-Lüneburg and the Archbishopric." - (en.wikipedia.org 11.08.2021)
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