Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.
MARGRAVE
As described in historical dictionaries
Patronymica Britannica (1860)
MARGRAVE. Germ, mnrligraf, an office and title of dignity, of common origin with marquis, or lord marcher — one who had charge of the frontier of the country.