Oliver

English, Scottish, Welsh, and German: from the Old French personal name Olivier, which was taken to England by the Normans from France. It was popular throughout Europe in the Middle Ages as having been borne by one of Charlemagne's paladins, the faithful friend of Roland, about whose exploits there were many popular romances. The name ostensibly means ‘olive tree’ (see Oliveira), but this is almost certainly the result of folk etymology working on an unidentified Germanic personal name, perhaps a cognate of Alvaro. The surname is also borne by Jews, apparently as an adoption of the non-Jewish surname.