History of Poland during the Piast dynasty of Lesser Poland, the country of the Vistulans, and of Silesia (both taken by Mieszko from the Czech state during the later part of the 10th century), Mieszko's state reached its mature form, including the main regions regarded as ethnically Polish. The Piast lands totaled about in area, with an approximate population of under one million. Initially a pagan, Mieszko I was the first ruler of the Polans tribal union known from contemporary written sources. A detailed account of aspects of Mieszko's early reign was given by Ibrâhîm ibn Ya`qûb, a Jewish traveler, according to whom Mieszko was one of
Mieszko I Tanglefoot p. 876). This is the oldest preserved record of the Mieszko's nickname in the form of "Plątonogi". From 1146, after the deposition of his father, Mieszko and his family mainly lived in the town of Altenburg in Saxony, which was granted as a temporary possession to Władysław II by his brother-in-law, King Conrad III of Germany. During his time in exile, Mieszko studied in Michaelsberg and Bamberg. However, the supposed temporary exile was, for the deposed High Duke, for good; he died in Altenburg in 1159. His sons continued the fight to recover their inheritance, and finally three years later,