Tags: Noble.
John Frederick (German: Johann Friedrich; 25 April 1625 Herzberg am Harz – 18 December 1679 Augsburg) was duke of Brunswick-Lüneburg and ruled over the Principality of Calenberg a subdivision of the duchy from 1665 until his death.The third son of George Duke of Brunswick-Lüneburg John converted to the Roman Catholic Church as the only member of his family in 1651. He received Calenberg when his elder brother George William inherited the Principality of Lüneburg.
