Ernestine Duchies

The Ernestine duchies, also called the Saxon duchies (but the Albertine appanage duchies of Weissenfels, Merseburg and Zeitz were also "Saxon duchies" and adjacent to several Ernestine ones), were a changing number of small states largely located in the present German state of Thuringia, governed by dukes of the Ernestine line of the House of Wettin.

The Saxon duchy began fragmenting in the 15th century as a result of the old German succession law that divided inheritances among all sons. All sons of a Saxon duke also inherited the title of Duke. Brothers sometimes ruled the territory inherited from their father jointly, and they sometimes split it up. Some of the Ernestine duchies retained their separate existence until 1918. Similar events in the houses of Reuss and Schwarzburg led to all of Thuringia becoming a tangle of small states from the late 15th century until the early 20th century.

Count Bernhard of Anhalt, youngest son of Albert "the Bear" (1106–70), inherited parts of the old Saxon duchy, primarily around Lauenburg and Wittenberg, in 1180. He had two sons, Albert and Henry. Albert inherited the Duchy of Saxony. In 1260 Albert bequeathed the duchy to his sons John I and Albert II, who gradually divided Saxony into the duchies of Saxe-Lauenburg and Saxe-Wittenberg with definite effect of 1296. Saxe-Wittenberg was recognized as the electorate of Saxony in the Golden Bull of 1356. When the last duke of Saxe-Wittenberg died without heir in 1422, the Emperor Sigismund gave the duchy to Frederick IV of the house of Wettin, Margrave of Meissen and Landgrave of Thuringia, who thereby became Frederick I, Elector of Saxony. The name Saxony was then generally applied to all of the Wettin's domains, including those in Thuringia, because Saxony was a ducal title, highest they possessed, and all house members used it, although many of them held lands only in Thuringia. Frederick I was succeeded by his son, Frederick II.

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