Treaty of Leipzig
The Treaty of Leipzig was signed on August 26, 1485 between Elector Ernest of Saxony and his younger brother Albert III, sons of Elector Frederick II of Saxony from the House of Wettin.
In 1423 Ernest's and Albert's grandfather, Margrave Frederick IV of Meissen had acquired the Saxon Electorate from Emperor Sigismund of Luxembourg. The Electorate - former Duchy of Saxe-Wittenberg - together with the incorporated Margraviate of Meissen and Landgraviate of Thuringia formed the united Wettin lands until the 1485 Leipzig partition. Based on the terms of the treaty, the lands were divided into two realms whereby Ernest acquired most of the western Thuringian regions and the former Duchy of Saxe-Wittenberg including the electoral dignity, while Duke Albert obtained the eastern territory of the former Margraviate of Meissen.
Elector Ernest established the town of Wittenberg as the capital of Ernestine Saxony and proclaimed himself Landgrave of Thuringia. Duke Albert established Meissen as the centre of Albertine Saxony and deemed himself Margrave of Meissen.
In the course of the Protestant Reformation the Ernestine and Albertine branch of the Wettin dynasty found themselves on different sides of the 1546/47 Schmalkaldic War. The Albertine Duke Maurice of Saxony as an ally of victorious Emperor Charles V of Habsburg was able to gain the Wittenberg territory and the electoral dignity, after his defeated Ernestine cousin Elector John Frederick I had to sign the Capitulation of Wittenberg. From that time on the Albertine line in the former Meissen Margraviate ruled the Electorate and later Kingdom of Saxony. The descendants of John Frederick I retained the Thuringian territory which split into numerous Ernestine duchies.
When after World War I the House of Wettin was deposed, the Albertine Saxon Kingdom was succeeded by the Free State of Saxony, while the former Ernestine duchies formed the Free State of Thuringia.
