"While he was the first Christian ruler of Poland, he continued the policies of both his father and grandfather, who initiated the process of creation of the Polish state. Through both alliances and the use of military force, Mieszko extended ongoing Polish conquests and early in his reign subjugated Kuyavia and probably Gdańsk Pomerania and Masovia. For most of his reign, Mieszko I was involved in warfare for the control of Western Pomerania, eventually conquering it up to the vicinity of the lower Oder river. During the last years of his life, he fought the Bohemian state, winning Silesia and probably Lesser Poland." - (en.wikipedia.org 31.01.2020)
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