Mieszko II Lambert by the chronicles of Gottfried of Viterbo, refers to Bezprym. However, the historians now think that he was killed in a plot hatched by the aristocracy. He was buried in the Cathedral of St. Peter and St. Paul. After Mieszko II's death, Poland's peasants revolted in a "pagan reaction." The exact reasons and date are unknown. Mieszko II's only son and heir, Casimir I, was either expelled by this insurrection, or the insurrection was caused by the aristocracy's expulsion of him. Some modern historians argue that the insurrection was caused more by economic than by religious issues, such as new
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,