Vladislaus I of Opole
Vladislaus I of Opole (c. 1225–1282), second son of Casimir I of Opole, received Kalisz and Wieluń as his share in 1234 but lost both to Greater Poland by 1249. In 1246 he inherited Opole-Racibórz from his brother Mieszko II the Fat. He first sided with Hungary, then switched in 1255 to Ottokar II of Bohemia and fought for him in 1260.
His 1273 bid for the Kraków throne ended in defeat. He founded numerous monasteries and granted Magdeburg Law to the towns of his duchy.