Origin of the name ERMENGARDE.
Etymology of the
Meaning of the baby name ERMENGARDE.
French form of Old German Ermengard
(q.v.), meaning "public guard." This was the name of the wife of the emperor Louis le
Debonnaire. Also see Anglo-Saxon Eormengeard.
Anglo-Saxonicum, Searle, 1897).
Ermengarde of Hesbaye (d. 818), was Queen of the Franks
and Holy Roman Empress as wife to Emperor Louis I. Ermengarde of
Tours (d. 851), was the wife of Emperor Lothair I of the Franks. (Wiki)