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 took place on this occasion, the information on the return of the accord, acting for the good of the country and release of prisoners indicate that a conflict actually did occur. The marriage with Oda considerably affected the position and prestige of Mieszko, who entered the world of Saxon aristocracy. As a son-in-law of Margrave Dietrich, he gained an ally in one of the most influential politicians of the Holy Roman Empire. As the Margrave was a distant relative of the Emperor, Mieszko became a member of the circle connected to the imperial ruling house. Probably in the early 980s