The authors agree that this surname is peculiar to northwestern Italy, with presence in Turin and in the Cuneo area —particularly in Mondovì—, an important cluster in Imperia and its surroundings —Pieve di Teco, Chiusanico— and another in Genoa and in Albenga, in the Savona area.

As for the etymology, E. De Felice and E. Rossoni agree in deriving it from the medieval name Brunengus or Bruningus, of Germanic-Burgundian origin, documented in the Codice Diplomatico della Lombardia medievale in a deed of the year 986 coming from the Lodi area. De Felice specifies that the base is the Germanic root brûn, which alludes to the dark colour of the complexion or the hair, and that the suffix -engus / -ingus is typical of the Germanic anthroponymy of Burgundian-Lombard origin, with a patronymic value equivalent to "descendant of the clan of". He also notes that this same root generated numerous related medieval Italian surnames, such as Bruni, Brunelli, Brunetti, Brunello and Brunini.