Mieszko I of Poland Mieszko I of Poland Mieszko I (; – 25 May 992) was the ruler of the Polans from about 960 until his death. A member of the Piast dynasty, he was a son of the legendary Siemomysł, and a grandson of Lestek. He was the father of Bolesław I the Brave (the first crowned king of Poland) and of Gunhild of Wenden. Most sources make Mieszko I the father of Sigrid the Haughty, a Nordic queen, though one source identifies her father as Skoglar Toste, and the grandfather of Canute the Great (Gundhild's son), and the great-grandfather of Gunhilda of
Mieszko I of Poland situation at that time. Another debatable point is Thietmar's claim that Mieszko "subordinated himself to the King". Most historians believe that it was only a matter of recognition of Otto's royal authority. Some suggest that a fealty relationship could in fact be involved. Whether or not the German-Polish invasion of Bohemia actually happened, the friendly relations between the Czechs and the Poles came to an end. Bohemia resumed its earlier alliance with the Lutici, which caused in 990 a war with Mieszko, who was supported by Empress Theophanu. Duke Boleslav II was probably the first one to attack. As a