Margrave

noun

1. A feudal era military-administrative officer of comital rank in the Carolingian empire and some successor states, originally in charge of a border area.

   "1973: Among pulverised heads of stone margraves and electors, reconnoitering a likely-looking cabbage patch, all of a sudden Slothrop picks up the scent of an unmistakable no it can’t be yes it is it’s a REEFER! — Thomas Pynchon, Gravity’s Rainbow"

2. A hereditary ruling prince in certain feudal states of the Holy Roman Empire and elsewhere; the titular equivalent became known as marquis or marquess.