 The diocese encompassed areas on both sides of the Oder River around the town of Lebus/Lubusz later called Lubusz Land.The diocese was established about 1125 by the Piast Duke Bolesław III Wrymouth of Poland in the westernmost region of Poland in the lands west of Greater Poland settled by pagan Polabian Slavs, in order to counter the eastward expansion of the Holy Roman Empire expedited by Emperor Henry V and the Archbishopric of Magdeburg.Duke Bolesław prompted the construction of St. Adalbert Cathedral in Lubusz, consecrated to the diocesan patron saint Adalbert of Prague, which was later destroyed.