The name “Julius” does not appear in the New Testament at all, and it does not appear in Josephus’ Wars of the Jews either despite many confusing references to other Caesars. As in Mark and Matthew, Wars only uses Caesar as a royal title, never connecting it to the “Julius” that supposedly gave it such great importance. Josephus first introduces Caesar as a title of Titus Flavius, then later describes the ascension and assassination of two Caesars without ever using the name Julius. The other Caesar is named Sextus Caesar, “a kinsman of the great Caesar”. These two were succeeded by the “younger Caesar”, who becomes of course, simply, Caesar. In Wars, Josephus names all the Emperors of the Julio Claudian dynasty: Augustus, Tiberius, Caius (i.e. Caligula), Claudius, and Nero. But he never names Julius.
The first Caesar mentioned by Josephus is Titus: “they were the tyrants among the Jews who brought the Roman power upon us, who unwillingly attacked us, and occasioned the burning of our holy temple, Titus Caesar, who destroyed it, is himself a witness, who, during the entire war, pitied the [Jewish] people” (Wars P:4). Josephus argues that the Jews deserved the destruction of Jerusalem by Titus, just as they deserved the destruction of the “first” temple by Nebuchadnezzar centuries before. Josephus concludes in his prologue, “it appears to me that the misfortunes of all men, from the beginning of the world, if they be compared to these of the Jews are not so considerable as they were”. It’s the same sob story all over again.
The characterization of Titus’ compassion for the Jewish commoners in his war against the Jewish tyrants fits with his role as a savior of the Jewish people. This compassion and salvation is mirrored by Jesus Christ himself, who supposedly predicted that within a generation of his ministry, the temple of the Jews would be ruined without one stone left upon another, and Jerusalem consumed in both civil and divine fury. Jesus was supposedly executed by Pilate around 30 CE, and indeed 40 years later, Titus fulfilled Jesus’ prophecies about the second coming. To both the gospels and Josephus, the Flavians were Messiahs.
Josephus also describes some of the history of “Julius” Caesar in Wars without using the name Julius: “Now, upon the flight of Pompey and of the senate beyond the Ionian Sea, Caesar got Rome and the empire under his power” (Wars 1.9.1). Soon after “There was at this time a mighty war raised among the Romans upon the sudden and treacherous slaughter of Caesar by Cassius and Brutus” (Wars 1.11.1). This last verse immediately follows the assassination of Sextus Caesar, with both murders described as a “treacherous slaughter”. So why won’t Josephus throw us a Julius in Wars?
Josephus devotes a whole chapter to Julius Caesar in Antiquities of the Jews, which was supposedly published about 20 years later than Wars, in 94 CE. Antiquities names Julius Caesar 5 times, and speaks for him in the first person no less. Julius establishes an eternal Jewish ethnic priesthood and exempts them from taxation:
Gaius Julius Caesar, imperator and high priest, and dictator the second time, to the magistrates, senate, and people of Sidon, sendeth greeting. If you be in health, it is well. I also and the army are well. I have sent you a copy of that decree, registered on the tables, which concerns Hyrcanus, the son of Alexander, the high priest and ethnarch of the Jews […] It is as follows: I Julius Caesar, imperator the second time, and high priest, have made this decree, with the approbation of the senate. […] I will that Hyrcanus, the son of Alexander, and his children, be ethnarchs of the Jews, and have the high priesthood of the Jews for ever, according to the customs of their forefathers […] And I think it not proper that they should be obliged to find us winter quarters, or that any money should be required of them (Antiquities 14:10:2).
Josephus also tells us about “Pilate”, which helps situate his histories beside the evolving Christian gospels. In Wars, Pilate harasses the Jews with imperial idols: “Pilate, who was sent as procurator into Judea by Tiberius, sent by night those images of Caesar that are called ensigns into Jerusalem” (Wars 9:2). These Caesarean idols agitate the iconoclastic Jews “as indications that their laws were trodden under foot”, and they appeal to Pilate to remove the idols, but Pilate refuses. The next day, Pilate calls all the Jews together and surrounds them with his swordsmen, threatening to chop them up if they do not accept the images of Caesar. The Jews fall down and expose their necks, preferring death to idolatry. Impressed, Pilate yields and removes the ensigns of Caesar (Wars 9:3). Pilate concludes his role in Wars by disguising his soldiers as commoners armed with staves to beat and kill Jews protesting his expenditure of their sacred treasure upon aqueducts (Wars 9:4).
These tales of Pilate are repeated in Antiquities and immediately followed by the Flavian Testimony, an interpolated paraphrase of Luke’s gospel that was not known to Christian apologists until over 200 years later. Like Mark and Matthew, Josephus never mentions “Pontius” in Wars, but both Luke and Antiquities name Pilate as such. Pilate is scarcely attested elsewhere: Philo make two scant references to Pilate (not Pontius), telling the same story as Josephus. In the Annals of Tacitus, dated to 116 CE, “Pontius Pilate” is described as the executioner of Jesus, but like the Flavian testimony, this passage is a late interpolation. The coins credited to Pilate bear neither his name nor his visage. It appears that some author simply made him up.
Either Mark is based on Josephus or Josephus based on Mark: both speak simply of Caesar and Pilate and describe the destruction of Jerusalem utilizing the same motifs and terminology. Likewise, Luke (and Acts) is informed by Antiquities (and the rest of Jospehus’s ouevre). Yet Mark’s representation of Caesar and Pilate is the most primitive of all; Mark makes no explicit connection to Rome in his gospel or the “Julio” Claudian dynasty. Meanwhile Josephus is far from a credible historian; he is rather a deeply religious student of scripture. His writings have an explicit religious motive. Therefore it is not so easy to say who borrowed from whom. After all, “Pilate” in Latin means “Spearman”, a name better befitting Mark’s parable of execution on a stake than Josephus’s tale of idol worship controversy. What does Pilate signify in Greek or Aramaic?
The official history of Pilate in ancient literature looks like this: he is introduced by Josephus in 75 CE, borrowed by Mark in 80, first named as Pontius in Antiquities in 94, possibly also by Marcion in 144, and Luke in 170. It is interesting that Wars mentions only Caesar and Pilate, while Antiquities mention Julius Caesar and Pontius Pilate. Interpolation and forgery must always be suspected when dealing with any of this literature. It could be that these scant references in Antiquities are anachronistic.
Regardless, Josephus invented the “great” Caesar and his resultant imperial dynasty before anyone thought to call him Julius. This supports my thesis that Julius Caesar was a later invention. Josephus is not only a father of Jewish history, he is possibly the father of imperial Roman history and thus Christian history as well. Either Mark or Josephus should be credited as the first author to use the terms Caesar and Pilate. History is written by the victors, and Josephus was writing for a family who had just conquered both Rome and Jerusalem in a civil war.
Can it be a coincidence that the birth of Julius Caesar is 100 years before the birth of Jesus Christ, or the birth of the Roman Empire is 100 years before the triumph of the Flavians at Masada? It seems that Josephus’ first task was to add a century to the pedigree of the imperial cult, which is why Wars knows all about the first five emperors of Rome, but nothing about a person named Julius. Pilate in Wars and Pilate in Mark bear little resemblance, but like the idolatrous images of Caesar in Wars, Christ as divine king is rejected by the Pharisees and Pilate is tasked with his removal. Mark often tells us about the importance of interpreting parables. Is Mark a parable of Josephus’ history, a tale of a royal idol rejected by the Jews?
It could be the case that Josephus was repeating Roman lore about Julius (like someone today would about the "glorious" and "beloved" US president and martyr Abraham Lincoln); i.e., it's just what the Romans were taught of their history. Also, one of the authors I've read on this subject wrote that until the Middle Ages, New Testaments always included Josephus as well, which is telling, I think. Because of the growing power and importance of the Church and its much-argued-over teachings, ensuring that the new Christian scriptures agree w/ those (later) teachings makes both the New Testament and the extracanonical writings as they've come down to us hugely suspect; lots of "changes" (usually called scribal errors) found their way into them over the centuries, many even admitted to by scholars.
Have you looked into Laurent Guyenot's take on Julius? He says that he's a fake character as well. And then there are the parallels of Julius' story and Jesus'.