 These acts by the bishop , and any frustration Buchan may have felt about the <unk> of his brother Robert Stewart , Earl of Fife as guardian of Scotland , may have caused him to react <unk> : in May , he descended from his island castle on <unk> and burned the town of <unk> , followed in June by the burning of Elgin and the cathedral with its manses . It is believed that he also burned <unk> Priory at this time , which was officially under the Bishop 's protection . Bur wrote to Robert III seeking reparation for his brother 's actions in a letter stating : 
