Flavius Josephus, Antiquities of the Jews
William Whiston, A.M., Ed.

[386] And this was the principal instance of Antony's affection for Herod, that he not only procured him a kingdom which he did not expect, (for he did not come with an intention to ask the kingdom for himself, which he did not suppose the Romans would grant him, who used to bestow it on some of the royal family, but intended to desire it for his wife's brother, who was grandson by his father to Aristobulus, and to Hyrcanus by his mother,) but that he procured it for him so suddenly, that he obtained what he did not expect, and departed out of Italy in so few days as seven in all. This young man [the grandson] Herod afterward took care to have slain, as we shall show in its proper place. But when the senate was dissolved, Antony and Caesar went out of the senate house with Herod between them, and with the consuls and other magistrates before them, in order to offer sacrifices, and to lay up their decrees in the capitol. Antony also feasted Herod the first day of his reign. And thus did this man receive the kingdom, having obtained it on the hundred and eighty-fourth olympiad, when Caius Domitius Calvinus was consul the second time, and Caius Asinius Pollio [the first time].