Dictionary of Medieval Names
from European Sources

Bertrad m. Old High German beraht, Old Saxon berht 'bright' from Proto-Germanic *berhtaz + Old Saxon rād, Old High German rāt 'counsel, advice'.

France
Latin
c823 Bertradus (nom) irminon-vol2 109, Palatiolum, Bertraus (nom) ibid. 6, Gaugiacum
Cite as: S.L. Uckelman. "Bertrad". In S.L. Uckelman, ed. The Dictionary of Medieval Names from European Sources, Edition 2016, no. 4. http://dmnes.org/2016/4/name/Bertrad.