Dictionary of Medieval Names
from European Sources

Frotbert m. Old Frisian, Old Saxon frōd, Old High German fruot 'wise' + Old High German beraht, Old Saxon berht 'bright' from Proto-Germanic *berhtaz.

France
Latin
657 Frodoberto (dat) DCEL-2 CCCXXIX, Frodobertus (nom) ibid. CCCXXIX
Cite as: S.L. Uckelman. "Frotbert". In S.L. Uckelman, ed. The Dictionary of Medieval Names from European Sources, Edition 2016, no. 4. http://dmnes.org/2016/4/name/Frotbert.