Roman Provincial - Syria: Kingdom of Commagene
The Kingdom of Commagene was independent from 162 BC until the death of Antiochos III in 17 AD. Commagene was then annexed by Tiberius until Caligula restored the kingdom for his friend, Antiochos IV in 38. Vespasian, in 72, reduced the kingdom permanently to provincial status after Antiochos IV was deposed for supposedly conspiring with the Parthians against Rome.
Antiochos IV, Epiphanes, AE29 of Samosata, 38-72, Syria-Kingdom of Commagene. BASILEYS ME ANTIOXOS EPI Diademed bust right, anchor countermark. KOMMAG_HNWN Scorpion and inscription in laurel wreath. Sear GIC 5507. Ex. Time Machine.Notes from Richard Baker and Oliver Hoover on the Moneta-L list:
The countermark is an oval, within is an ancient Anchor, with "A" in left field ( not readily visible ) and "N" in right field. It is a cmk. for Antiochus IV, possibly giving the coin the equivalent of a Dupondius. Struck between 69-72 according to Howgego, #373. A dynastic badge meant to show continuity with the Seleucid dynasty. Found on coins of Antiochus IV, Iotape ( his Queen ), Nero, Claudius and Otho (Richard Baker).
The fact of the matter is that countermarks were applied to provincial bronze coins for a wide range of reasons. Although propaganda was a reason to countermark, there were also quite a few other fiscal, political and military motives for countermarking. See Howgego for a lengthy discussion of the reasons for countermarking in the Roman provinces. In the case of your coin, it seems likely that the countermark was applied for some fiscal reason. By requiring people to get their coins countermarked for a fee governments could raise additional funds. The anchor is not used here to advertise the legitimacy of Antiochus IV as a descendant of the Seleucids. It is simply a Commegenean state seal (inherited from the Seleucids) applied to the coin to indicate that the fee had been paid and that the coin was therefore in good standing (Oliver Hoover).