It was through the influence of his sister and nephew that Paul was appointed bishop sometime before October 1261. He succeeded Opizo, who is last mentioned in July 1259 and probably died around the time of the Mongol invasion of 1260. Opizo had excommunicated Bohemond VI, but Pope Urban IV granted Paul wide latitude in dealing with his nephew while the case was "sub judice". Paul's influence brought many Roman knights into Bohemond's service.