Mieszko I of Poland Denmark, Canute the Great's daughter and wife of Henry III, Holy Roman Emperor. The first Christian ruler of territories later called Poland, Mieszko I is considered the creator of the Polish state. He continued the policy of both his father and grandfather, who were rulers of the pagan tribes located in the area of present-day Greater Poland. 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
Mieszko I of Poland in the hands of Bohemia. Sandomierz under this scenario was the central hub of the area, with Czerwień, Przemyśl and Chełm assuming the function of defensive borderland strongholds. After the death of Emperor Otto I in 973 Mieszko, like his brother-in-law, Duke Boleslav II of Bohemia, joined the German opposition in support of the attempted imperial succession of Henry II, Duke of Bavaria. Mieszko may have been motivated by revenge because of the (presumably) negative verdict of the Quedlinburg summit, but, more importantly, he may have wanted more favorable terms for his cooperation with Germany. The participation of Mieszko in