Mieszko I of Poland and half a century later, by Bishop Thietmar of Merseburg. By the time Mieszko I took over from his father, the Polans' tribal federation of Greater Poland had for some time been actively expanding. Continuing this process, perhaps in the first years of Mieszko's reign, if it had not been done already by his father, Mieszko I conquered Masovia. Likely also during that period or earlier, at least partially Gdańsk Pomerania was obtained. Mieszko's interests were then concentrated mainly on areas occupied by the eastern (near the Oder River) branches of the Polabian Slavs; some of them became soon subordinated
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