Herzogtum Glogau
In 1412 was the formal division of their Duchy: Jan I retained Żagań and Wenceslaus, together with his brother Henry IX the Older and Henry X Rumpold obtained Głogów as co-rulers. In 1417 was made a new division, this time in the Duchy of Głogów: Henry IX the Older and Henry X Rumpold retained Głogów and Szprotawa, and Wenceslaus received the towns of Krosno Odrzańskie, Świebodzin and Bytnica.