Poland to form into a recognizable unitary and territorial entity around the middle of the 10th century under the Piast dynasty. Poland's first historically documented ruler, Mieszko I, accepted Christianity with the Baptism of Poland in 966, as the new official religion of his subjects. The bulk of the population converted in the course of the next few centuries. In 1000, Boleslaw the Brave, continuing the policy of his father Mieszko, held a Congress of Gniezno and created the metropolis of Gniezno and the dioceses of Kraków, Kołobrzeg, and Wrocław. However, the pagan unrest led to the transfer of the capital
Mieszko I Tanglefoot the Sandomierz nobles captured in the battle). On 22 March 1201 Jarosław of Opole died. The Duchy of Opole was then inherited by his father Bolesław the Tall, with whom the late Duke was recently reconciled. Bolesław the Tall died only nine months later, on 7/8 December 1201, leaving all his lands to his eldest (and only) surviving son Henry I the Bearded. Mieszko was determined to obtain Opole and made a surprise attack at the beginning of 1202. The Duke managed to obtain Opole, which was from then on definitely joined to his lands. Despite this victory, Mieszko wanted