Mieszko the Younger time in 1166 or 1167 in a document signed between Mieszko III and Casimir II the Just at the congress in Jędrzejów as one of the sons of the Duke of Greater Poland. Between 1177 and 1179, as a result of the revolt against his father, Mieszko, with his parents and siblings, were exiled from Poland. They probably returned to the country in 1181, when Mieszko III regained the rule over Greater Poland. In 1184 and thanks to the wise diplomatic affairs of his father, Mieszko the Younger was appointed by the sickly Duke Leszek Governor of the Masovian-Kuyavian principality,
Mieszko I of Poland responsible according to Gallus Anonymus, who claimed that it was the Bohemian Princess Dobrawa who convinced her husband to change his religion. Likewise chronicler Thietmar attributes Mieszko's conversion to Dobrawa's influence. There are no reasons to negate Dobrawa's role in Mieszko's acceptance of Roman Catholicism; however crediting rulers' wives with positive influence over their husbands' actions was a common convention at that time. It is generally recognized that the baptism of Mieszko I took place in 966. The place is unknown; it could have had happened in any of the cities of the Empire (possibly Regensburg), but also in one