Mieszko II Lambert of Pöhlde asked the Emperor to defend against the attacks of Mieszko II, promising support in the fight against the Polish ruler. Despite the treaty which secured peace between Poland and Germany, the Emperor soon armed a retaliatory expedition against Mieszko II. Conrad II's army arrived to Lusatia in the autumn of 1029 and began the siege of Bautzen; but the German troops did not receive the promised support of the Lutici tribe and the expedition failed. Threatened by the Hungarians, the Emperor was forced to retreat. Probably in this same year the son of Oldřich, Bretislaus I, attacked and
Mieszko I, Duke of Cieszyn the Přemyslid dynasty in the person of Wenceslaus III, son and successor of Wenceslaus II. On 5 October 1305, Mieszko obtained his major victory when his daughter Viola Elisabeth married King Wenceslaus III. This union was a chance for Mieszko to make himself one of the most powerful figures in Bohemia, and he even began some attempts to obtain the Polish crown. However, Mieszko's promising career ended suddenly with the murder of Wenceslaus III (Olomouc, 4 August 1306). Viola Elisabeth never bore Wenceslaus III any children and the Přemyslid dynasty became extinct. After 1306 the political activity of Mieszko almost