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, Duke of Cieszyn was on 1 January 1290. In internal politics he pursued vigorous policies. Mieszko carried out intensive colonizing policies and founded many settlements. He also gave city rights to several towns: Cieszyn, Oświęcim (in 1291), Bielsko, Skoczów and Fryštát. On 10 November 1292 he granted the city rights to Zator. Mieszko refused to support any of the Piast pretenders to the Polish throne (Henry IV Probus, Przemysł II and Władysław I the Elbow-high). Instead he stood alongside King Wenceslaus II of Bohemia. On 17 January 1291 the formal agreement was signed in Olomouc which formed the alliance between the Bohemian Kingdom,