"Friedrich Wilhelm III (b. Altenburg, 12 July 1657 – d. Altenburg, 14 April 1672), was a duke of Saxe-Altenburg.
He was the second son of Friedrich Wilhelm II, Duke of Saxe-Altenburg and Magdalene Sybille of Saxony, his second wife." - (en.wikipedia.org 06.03.2020)
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