1881, "belonging to the Frankish royal and imperial dynasty founded by Charles Martel, from Medieval Latin Carolus "Charles" (a name from the common Germanic noun meaning "man, husband;" see carl). Also compare Carlovingian.
"of or pertaining to the dynasty to which the first French kings belonged," 1690s, from French Mérovingien, from Medieval Latin Merovingi, "descendants of Meroveus," (mythical?) ancestor of the line of Frankish kings in Gaul c. 500-752 beginning with Clovis; Merovingi is a Latinization of his Germanic name (compare Old High German Mar-wig "famed-fight") with the Germanic patronymic suffix -ing.
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<a href="https://www.etymonline.com/word/Carlovingian">Etymology of Carlovingian by etymonline</a>
Harper, D. (n.d.). Etymology of Carlovingian. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/Carlovingian