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 of Poland As a result, in 965 Mieszko I married his daughter Dobrawa (also named "Dobrava", "Doubravka" or "Dąbrówka"). This political Polish-Bohemian alliance is likely to have been initiated by the Polish ruler. It is probable that the marriage was officially arranged in February 965. The next step was the baptism of Mieszko. There are different hypotheses concerning this event. Most often it is assumed that it was a political decision, intended to bring Mieszko's state closer to the Czechs and to facilitate his activities in the Polabian Slavs area. At the same time, the baptism decreased the likelihood of future attacks