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 responsible according to Gallus Anonymus, who claimed that it was the Bohemian Princess Dobrawa who convinced her husband to change his religion. Likewise chronicler Thietmar attributes Mieszko's conversion to Dobrawa's influence. There are no reasons to negate Dobrawa's role in Mieszko's acceptance of Roman Catholicism; however crediting rulers' wives with positive influence over their husbands' actions was a common convention at that time. It is generally recognized that the baptism of Mieszko I took place in 966. The place is unknown; it could have had happened in any of the cities of the Empire (possibly Regensburg), but also in one