English and Dutch: from Latin Marcus, the personal name of St. Mark the Evangelist, author of the second Gospel. The name was borne also by a number of other early Christian saints. Marcus was an old Roman name, of uncertain (possibly non-Italic) etymology; it may have some connection with the name of the war god Mars. Compare Martin. The personal name was not as popular in England in the Middle Ages as it was on the Continent, especially in Italy, where the evangelist became the patron of Venice and the Venetian Republic, and was allegedly buried at Aquileia. As an American family name, this has absorbed cognate and similar names from other European languages, including Greek Markos and Slavic Marek.