"Albrecht, Duke of Saxe-Eisenach, (Altenburg, 27 July 1599 – Eisenach, 20 December 1644) was a ruler of the duchy of Saxe-Eisenach. He was the seventh (but fourth surviving) son of Johann, Duke of Saxe-Weimar, and Dorothea Maria of Anhalt. His regnal name Albert IV derives from the numbering of the duchy of Saxony as a whole, not specifically to the succession in Saxe-Eisenach.
Albrecht received his first instruction from the Field Marshal Frederick of Kospoth. Later he studied at the University of Jena with his brothers.
In the years 1619-1621 he completed his Cavalierstour (Study Tour) with his younger brother Johann Frederick. The two princes travelled to France and Switzerland." - (en.wikipedia.org 31.10.2019)
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