The Duchy of Silesia was first split into lower and upper parts in 1172 during the period of Poland's feudal fragmentation, when the land was divided between two sons of former High Duke Władysław II. The elder Bolesław the Tall ruled over Lower Silesia with his capital in Wrocław (then known as Vratislav, Wrotizla, or Prezla), and younger Mieszko Tanglefoot ruled over Upper Silesia with his capital at first in Racibórz, from 1202 in Opole. Later Silesia was divided into as many as 17 duchies. Main duchies of Lower Silesia: