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 of the Polish towns like Gniezno or Ostrów Lednicki. The belief that the baptism was accomplished through the Czechs in order to avoid the dependence on Germany and the German Church is incorrect, because Bohemia would not have its own church organization until 973. At the time of the baptism of Mieszko the existing Bohemian church establishment was a part of the Regensburg diocese. Thus, if the Polish ruler accepted the baptism through Prague's mediation, it had to be sanctioned in Regensburg. However, the religious vocabulary (words like baptism, sermon, prayer, church, apostle, bishop or confirmation) were adopted from the