fem. proper name, from Latin Marcia, fem. of Marcius, a Roman gens name, related to Marcus (q.v.).
Anglo-Saxon kingdom of the Midlands, Latinized from Old English Mierce "men of the Marches," from mearc (see march (n.2)). Related: Mercian. Mercian law (Medieval Latin Lex Merciorum, Middle English Mercene laue, mid-12c.) was the law code of the Anglo-Saxon kingdom of Mercia (perhaps codified by Offa, but it survives only in fragments quoted in later English laws). Eight shires in the old Mercia still were governed under it in Middle English times, and the laws of William the Conqueror and Henry I set different penalties for breaches of the peace between the Mercian law, the Dane law, and the West Saxon law. Through some whim or error, Geoffrey of Monmouth and other later Middle English writers invented a British queen, Marcia, and attributed the laws to her.