Gilbert allegedly had a younger brother, Richard de Moravia, who was killed fighting against Scandinavians and whose effigy-sarcophagus currently resides in the cathedral.

King Alexander probably decided that, after the murder of Gilbert's predecessor Adam of Melrose, the bishopric's seat (cathedra) should be moved closer to royal protection.

Gilbert nevertheless continued to reside for much of his episcopate in the more violent north, and maintained a palace at Scrabster.

Gilbert's achievements include the building of the cathedral at Dornoch, and the establishment of several hospices for the poor.

Folklore surrounding St Gilbert was collected in Sutherlandshire in the late nineteenth century, including a legend of how he overcame a dragon—or salamander—that was terrorising the country.