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 of Poland been between 922–945; the activity of the Duke in his final years of life puts the date of his birth closer to the latter year. There are three major theories concerning the origin and meaning of Mieszko I's name. The most popular theory, proposed by Jan Długosz, explains that Mieszko is a diminutive of "Mieczysław", a combination of two elements or lexemes: "Miecz" meaning sword and "Sław" meaning famous. Today, this theory is rejected by the majority of Polish historians, who consider the name Mieczysław to have been invented by Długosz to explain the origin of the name Mieszko. Today,