publican:  The modern use of publican for ‘innkeeper’ dates from the early 18th century, and presumably arose from an association with public house. Its original meaning was ‘tax collector’. It comes via Old French publicain from Latin pūblicānus ‘person who paid for the privilege of collecting the public revenues, in return for a percentage’. This in turn was derived from pūblicum ‘public revenue’, a noun use of pūblicus ‘public’ (source of English public).
c. 1200, "tax-gatherer," from Old French publician (12c.), from Latin publicanus "a tax collector," noun use of an adjective, "pertaining to public revenue," from publicum "public revenue," noun use of neuter of publicus (see public (adj.)). Original sense in Matt. xviii:17, etc.; meaning "keeper of a pub" first recorded 1728, from public (house) + -an.