Mieszko I Tanglefoot brother Vladimir, Duke of Olomouc, son of Otto III Detleb. They had five children: Mieszko I Tanglefoot Mieszko IV Tanglefoot () (ca. 1130 – 16 May 1211) was Duke of Kraków and High Duke of Poland from 1202 and from 9 June 1210 until his death. He was also Duke of Silesia from 1163 to 1173 (with his brother as co-ruler), Duke of Racibórz from 1173 and Duke of Opole (as Mieszko I Tanglefoot). He was the second son of Władysław II the Exile by his wife Agnes of Babenberg, daughter of Margrave Leopold III of Austria and half-sister 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