Mieszko I of Poland death occurred from causes other than natural. According to Thietmar the Polish ruler died "in an old age, overcame with fever". Probably he was buried in the Poznań Cathedral. The remains of the first historical ruler of Poland have never been found and the place of his burial is not known with certainty. In 1836–1837 a cenotaph was built for Mieszko I and his successor Bolesław I the Brave in the Golden Chapel () at the Poznań Cathedral, where the damaged remains found in the 14th century tomb of Bolesław were placed. According to Thietmar Mieszko I divided his state
Mieszko I Tanglefoot to both Mieszko (who received the towns of Racibórz and Cieszyn) and Jarosław (who received Opole). In 1177 Mieszko supported his uncle and namesake Mieszko III the Old when he had to fight to maintain his rule over the Duchy of Kraków; this renewed again the disputes between him and Bolesław I the Tall, who wished to obtain the Duchy and with this the Seniorate. However, Bolesław suffered an unexpected defeat by Mieszko and his own son Jarosław, who distracted him to advance over Kraków; in his place was his younger uncle and ally, Casimir II the Just, who captured