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 of Poland Czech language and had to come from Dobrawa's entourage and the church elements that arrived with her. Perhaps with her also came the first Polish bishop, Jordan. It could be that the reason for the Czech preference of Mieszko was the existence in Bohemia of a mission which followed the precepts of the Byzantine Greek brothers and later saints Cyril and Methodius, who developed and performed the liturgy in the Slavic rite, more readily understood by Mieszko and his subjects. The Slavic rite church branch had survived in Bohemia for another hundred years after Mieszko's baptism. Through the adoption of