Mieszko I Tanglefoot the city and was proclaimed the new High Duke of Poland. Mieszko III the Old found himself in exile in Racibórz and it seemed that the war between Mieszko Tanglefoot and Casimir II the Just was now just a matter of time. Casimir II, however, went a different route and, in order to gain the favor of the Duke of Racibórz given him the towns of Oświęcim and Bytom (with the fortress of Oświęcim, Bytom, Mikołów, Siewierz and Pszczyna, although some historians estimate that these fortress had belonged to Mieszko only since 1179). On the other hand, Bolesław the Tall
Mieszko I, Duke of Cieszyn was on 1 January 1290. In internal politics he pursued vigorous policies. Mieszko carried out intensive colonizing policies and founded many settlements. He also gave city rights to several towns: Cieszyn, Oświęcim (in 1291), Bielsko, Skoczów and Fryštát. On 10 November 1292 he granted the city rights to Zator. Mieszko refused to support any of the Piast pretenders to the Polish throne (Henry IV Probus, Przemysł II and Władysław I the Elbow-high). Instead he stood alongside King Wenceslaus II of Bohemia. On 17 January 1291 the formal agreement was signed in Olomouc which formed the alliance between the Bohemian Kingdom,