Tigranes V and Erato
In the year 4 CE, the pro-Roman king Ariobarzanes of Armenia, who was not from Armenia but from Media Atropatene, died in an accident.note He was succeeded by his son Artavasdes III,note who was murdered two years later, perhaps because he did not belong to the Artaxiad dynasty. The Roman emperor Augustus sent Tigranes V to Armenia, a prince who did belong to the royal family of the Armenians.note (Several members of this dynasty had been taken captive in 34 BCE and were living in Italy.)
To strengthen his claim to the Armenian throne, Tigranes V married Erato, the queen of Tigranes IV (r. c.8 BCE - 1/2 CE), the last effectice ruler of Armenia. The Roman historian Tacitus is, apparently, only aware of the queen, mentioning that Armenia became leaderless "after an experiment in female government with a queen called Erato, who was quickly expelled".note
The statement is not only incomplete - Tacitus ignores the king - but also untrue, because after an interregnum without leader, Artaxias III Zenon (c.18-34 CE) was king.