Mieszko I, Duke of Cieszyn brothers in the consent of the foundation of a Cistercian abbey in Rudy. After his father's death in 1282, and according to the custom during the fragmentation of Poland, Mieszko and his brothers divided the Duchy of Opole-Racibórz between them: Mieszko and his youngest brother Przemysław received together the district of Racibórz as co-rulers. The other two brothers, Casimir and Bolko I, received Opole. Because Przemysław was still a minor at that time, Mieszko ruled alone until he attained his majority, in 1284. In 1285 Mieszko politically supported the Bishop of Wrocław, Thomas II Zaremba against Henry IV Probus, providing
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