John I of Rosenberg

John I of Rosenberg was the youngest son of Peter I of Rosenberg and Catherine of Vartenberk, of a leading Bohemian noble house. After his father died in 1347 his elder brothers ruled the family lands.

In 1367 the brothers founded an Augustinian monastery at Třeboň, and when the estates were divided in 1374 John took over their administration, residing at Třeboň and Český Krumlov. He died childless on 1 September 1389, never becoming regent.