John the Baptist arrested by Herod Antipas (see Herodian Dynasty chart in appendix First Century).
John was imprisoned in the Herodian fortress of Machaerus, about 9 miles east of the Dead Sea (in modern–day Jordan).
At this time, there was one preeminent center of power: Rome, as personified by Pontius Pilate. There were two significantly subordinate, nominal centers of power in greater Judea given a modicum of deference by Rome: Herod Antipas to the northeast in secular matters, and the Sadducees at the Temple in Temple matters. Both Herod Antipas and the Sadducees High Priest were implanted in Judea by Rome, served at Rome’s pleasure, and generally did nothing which might conceivably antagonize Rome.
There was another power center—the Jewish religious/nationalist /Zealot–alignment—most certainly not given any standing by Rome. Quite the contrary; it was poised and coiled against Rome and the Sadducee High Priest.
John was beheaded by Herod Antipas in the early 30s CE (precise year unknown) as a threat to the local order.