Mieszko I of Poland elders, and limited their authority. Clergy who arrived in the country contributed to the development of education and culture, and of the state administration and diplomacy, as well. At the end of Mieszko's reign (ca. 990), Poland began to pay tribute to the pope (Peter's Pence). However, the conversion of the Polish population to Catholicism was a long-term process, and was not completed during the reign of Mieszko I. The duke probably had to deal with rebellions led by the old pagan priest caste. In some villages, the old Slavic beliefs and customs were continued until the 16th century. After
Mieszko I of Poland Quedlinburg in 973 to explain and justify their conduct. The exact judgment of the Emperor is unknown, but it's certain that the sentence wasn't carried out because he died a few weeks after the Diet. It is commonly assumed that the sentence was unfavorable to the Polish ruler. The "Annals of Altaich" indicates that Mieszko was not present in Quedlinburg during the gathering; instead, he had to send his son Bolesław as a hostage. Mieszko's conflict with Odo I was a surprising event because, according to Thietmar, Mieszko respected the Margrave highly. Thietmar wrote the following: It is believed that