Josephus says Antipas "fell in love" with Herodias, his niece & sister-in-law. He suggested marriage. She agreed to wed IF he divorced his first wife AFTER returning from Rome. Indeed, Josephus says Antipas "transacted some business" (loeb) while there. He secured the rights to a mint and the right to break a longstanding treaty with Aretas, King of Nabatea.
Josephus does not strictly say that Herodias waited in Caesarea. If she did not make this voyage with Antipas, she must have written some letters - at least one to her Patron Antonia. In Rome, such a letter would have gotten Antipas an audience with Antonia, who at least had the power to put Herod in front of Sejanus, and probably Tiberius also. It seems most likely Antipas did see Capri.
The letter Antipas eventually wrote to Tiberius (AD 36) reflects that some kind of understanding had previously gone between them about Aretas and Galilee. It wasn't just Antipas' earned favor or Aretas' war crimes that moved Tiberius to send a Legion down for retribution. The assurance of Rome's power had been part of the bargain when Antipas asked for Herodias - when Antipas asked to divorce the Nabatean.
Why did Antipas want Herodias? Was love really a factor? Perhaps. Herodias' ambition, her connections, her Roman sensibility, her Latin (!), her genes, and the financial prospects of all that together - such attractive assets may have helped inspire the Tetrarch's great "love". She was quite the match for him, maybe more than a match.
Of Herodias' ambition, it did run in the blood. Her aunt Salome (HTG's sister) was once briefly the power behind Palestine's throne, for a few months in 4 BC. Herodias was a small child in Rome at that time, but may have visited with aunt Salome while the Herodian parties waited there for Augustus to rule on their succession dispute. At any rate, Herodias named her daughter (with husband #1) after that aunt, and later married that daughter to Philp the Tetrarch. That is some evidence of ambition.
That same royal ambition ironically resulted in Herodias' eventual downfall. Then again, her only real failures at that point may have been misjudging Caligula, and underestimating her brother. Apart from the Emperor's madness, Salome may have gotten her crown after all. If, indeed, things in 27 BC were as they seem to have been, Herodias was selected by Antipas - and approved of by Rome - to eventually become Queen of Galilee.
Fini. For now.
Read the Whole Series: Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Conclusion