Dictionary of Medieval Names
from European Sources

Berthard m. Old High German beraht, Old Saxon berht 'bright' from Proto-Germanic *berhtaz + Old Saxon hard, Old High German hart 'strong, hard'.

France
Latin
1115x1149 Brithardus (nom) CartStPC X
Cite as: S.L. Uckelman. "Berthard". In S.L. Uckelman, ed. The Dictionary of Medieval Names from European Sources, Edition 2017, no. 1. http://dmnes.org/2017/1/name/Berthard.