Saxon Brother War

The Saxon Fratricidal War (German: Sächsischer Bruderkrieg) was a war fought between the two brothers Frederick II, Elector of Saxony and Duke William III over Wettin ruled areas from 1446 to 1451. After a dispute over the division of certain family lands between Frederick II and William III, the Division of Altenburg eventually led to growing tensions between the two brothers and an inability to agree on who ruled which areas. After failed attempts at reconciliation, the war broke out and lasted for five years. The war was destructive and had no clear winner before being ended with a peace treaty at Naumburg. Following the war and subsequent divisions the Saxons lost much of their former power and influence within the different German states and families.

The House of Wettin and its line of Saxon princes gained a large amount of land over the years mainly through inheritance, including the Landgraviate of Thuringia, the Margraviate of Meissen, the Duchy of Saxony and the Electorate of Saxony. Frederick I was the Elector of Saxony and Margrave of Meissen and ruled over all of the lands except for the lands in Thuringia. Frederick I's cousin Frederick of Thuringia was Landgrave of Thuringia and ruled over those lands. When Frederick I died in 1428, his four sons Frederick II, Sigismund, Heinrich, and William III inherited his lands jointly. Heinrich died in 1435, and in 1440 Sigmisund became Bishop of Würzburg and renounced his claims to the land. Frederick, who was the eldest of the two remaining sons, now held the Electorate of Saxony and some land around Wittenberg in his own right, whilst throughout the remainder of the land he ruled together with William. This continued without serious incident for twelve years until, in 1440, Frederick of Thuringia died childless, and the two brothers inherited extensive land within Thuringia as well as the title of Landgrave of Thuringia.

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