"Friedrich Wilhelm II (Weimar, 12 February 1603 – Altenburg, 22 April 1669), was a duke of Saxe-Altenburg.
He was the youngest son of Friedrich Wilhelm I, Duke of Saxe-Weimar, and Anna Maria of the Palatinate-Neuburg, his second wife. He was born eight months after the death of his father, on 7 July 1602.
Shortly after his birth, Friedrich Wilhelm II and his older brothers inherited Saxe-Altenburg as co-rulers under the guardianship of the Electors of Saxony Christian II and John George I until 1618, when his older brother John Philip assumed the government of the duchy and the guardianship of his younger siblings." - (en.wikipedia.org 10.08.2021)
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