caribert of laon, son of martin of laon, was the grandfather of charlemagne. he was the father of charles's mother, bertrada of laon. in 721, he signed, with his mother bertrada of prüm, the foundation act of the abbey of prüm. the same year, also with his mother, he made a donation to the abbey of echternach. in 744, his daughter bertrada of laon (by bertrada of cologne) married pepin the short, mayor of the palace of neustria and burgundy and later king of the franks. he died before 762.