The surname Marx is a Germanic surname, believed to originate with Mark the Evangelist and the Roman praenomen Marcus, the latter deriving from the god Mars.
The similarly-spelled Marks may share etymology with march (territory), especially near Wales, but most British Marxes have Jewish roots, typically in the Rhineland or former Pale of Settlement.
[1] Famously, Karl Marx's father, born Herschel HaLevi Mordecai in Saarlouis, assimilated in 1817 or 1818 to Heinrich Marx because Prussia banned Jews from public service.
[2] Amateur geneologist Colin Shelley suggests that Marx' prevalence there may have arisen as a macaronic acronym for māšīaḥ rex.
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