Dictionary of Medieval Names
from European Sources

Lanthar m. Old High German lant, Old Saxon land 'land' + Old High German heri 'host, army'.

France
Latin
c823 Lantharius (nom) irminon-vol2 15, CE
Cite as: S.L. Uckelman. "Lanthar". In S.L. Uckelman, ed. The Dictionary of Medieval Names from European Sources, Edition 2016, no. 4. http://dmnes.org/2016/4/name/Lanthar.