Overview
The Julii Caesares were the most illustrious family of the patrician gens Julia. The family first appears in history during the Second Punic War, when Sextus Julius Caesar was praetor in Sicily. His son, Sextus Julius Caesar, obtained the consulship in 157 BC; but the most famous descendant of this stirps is Gaius Julius Caesar, a general who conquered Gaul and became the undisputed master of Rome following the Civil War. Having been granted dictatorial power by the Roman Senate and instituting a number of political and social reforms, he was assassinated in 44 BC. After overcoming several rivals, Caesar's adopted son and heir, Gaius Julius Caesar Octavianus, was proclaimed Augustus by the senate, inaugurating what became the Julio-Claudian line of Roman emperors.
History
The first of the Julii Caesares to appear in history was Sextus Julius Caesar, praetor in Sicily in 208 BC. From the filiation of his son, Sextus, "Sex. f. L. n.", we know that his father was named Lucius, but precisely who this Lucius was and whether he bore the surname Caesar is uncertain. On the assumption that the Caesares were descended from earlier notable families of the Julia gens, some scholars have suggested that he was the son of Lucius Julius Libo, consul in 267 BC.
The Dictionary of Greek and Roman Biography and Mythology says this of the cognomen Caesar:
It is uncertain which member of the Julia gens first obtained the surname of Caesar, but the first who occurs in history is Sextus Julius Caesar, praetor in BC 208. The origin of the name is equally uncertain. Spartianus, in his life of Aelius Verus, mentions four different opinions respecting its origin:
That the word signified an elephant in the language of the Moors, and was given as a surname to one of the Julii because he had killed an elephant.
That it was given to one of the Julii because he had been cut (caesus) out of his mother's womb after her death; or
Because he had been born with a great quantity of hair (caesaries) on his head; or
Because he had azure-colored (caesii) eyes of an almost supernatural kind.
Of these opinions the third, which is also given by Festus, seems to come nearest the truth. Caesar and caesaries are both probably connected with the Sanskrit kêsa, "hair", and it is quite in accordance with the Roman custom for a surname to be given to an individual from some peculiarity in his personal appearance.
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