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 Kazimierzowic "Gesta principum Polonorum" written in the early 12th century, put Mieszko third in order, among his brother. Modern historian, Janusz Bieniak, has supposed that Mieszko was the second son of Casimir I and was older than Władysław Herman, but most scholars disagree with this hypothesis. The date of Mieszko's birth was given by "Rocznik krakowski" (Kraków Annals). This source omitted dates of birth of Mieszko's brothers. Kazimierz Jasiński thought that "Rocznik" was started shortly before Mieszko's birth and this was the reason for absence of his older brothers. Przemysław Wiszewski supposed tha Casimir I chose Mieszko as his successor and