Wenceslaus I, d. 1253, king of Bohemia (1230–53), son and successor of Ottocar I. He invited large numbers of Germans to settle in the villages and towns of Bohemia and Moravia. In some villages peasants of Czech origin became a minority or were forced to submit to German-style feudal obligations. Many towns were granted self-rule, with charters modeled on that of Magdeburg. After resisting the invasion of Batu Khan (1241), Wenceslaus and his nobles built or rebuilt many castles, giving them German names. Wenceslaus received Holy Roman Emperor Frederick II's support in his attempt to acquire Austria but later backed Pope Gregory IX against the emperor. He was succeeded by his son, Ottocar II.