Ernestine and Albertine Wettins
The family divided into two ruling branches in 1485 when the sons of Frederick II, Elector of Saxony, divided the territories hitherto ruled jointly.
The elder son Ernest, who had succeeded his father as Prince-elector, received the territories assigned to the Elector (Electorate of Saxony) and Thuringia, while his younger brother Albert obtained the March of Meissen, which he ruled from Dresden. As Albert ruled under the title of "Duke of Saxony", his possessions were also known as Ducal Saxony.
The older, Ernestine branch remained predominant until 1547 and played an important role in the beginnings of the Protestant Reformation. Their predominance ended in the Schmalkaldic War, which pitted the Protestant Schmalkaldic League against Emperor Charles V. Although itself Protestant, the Albertine branch rallied to the Empire's cause; Charles V rewarded them by forcing the Ernestines to sign away their rights to the Electoral title and lands to the Albertines. The Ernestine line was thereafter restricted to Thuringia, and its dynastic unity swiftly crumbled.
The Albertine Wettin maintained most of the territorial integrity of Saxony, preserving it as a significant power in the region, and using small appanage fiefs for their cadet branches, few of which survived for significant lengths of time. The Ernestine Wettin, on the other hand, repeatedly subdivided their territory, creating an intricate patchwork of small duchies and counties in Thuringia.
The junior Albertine branch ruled as Electors (1547–1806) and Kings of Saxony (1806–1918) and also played a role in Polish history: two Wettin were Kings of Poland (between 1697–1763) and a third ruled the Duchy of Warsaw (1807–1814) as a satellite of Napoleon. After the Napoleonic Wars, the Albertine branch lost about 40% of its lands, including the old Electorate of Saxony, to Prussia, restricting it to a territory coextensive with the modern Saxony.
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