César m
French: from the old Roman family name Caesar, of uncertain meaning. It has been connected with Latin caesaries head of hair, but this is probably no more than folk etymology; the name may be of Etruscan origin. Its most notable bearer was Gaius Julius Caesar (?102–44 BC) and it also formed part of the full name of his relative Augustus (Gaius Julius Caesar Octavianus Augustus). Subsequently it was used as an imperial title and eventually became a vocabulary word for an emperor (leading to German Kaiser and Russian tsar).
First names dictionary. 2012.