[2] After living in political exile for a number of years, she co-ruled as Roman client queen from 6 until 12 with Tigranes V,[3] her distant paternal relative and possible second husband.

[9] In accordance with Oriental or Hellenistic custom, Tigranes IV married Erato in order to preserve the purity of the Artaxiad bloodline.

The discontent of the ruling Artaxiad monarchs and their subjects towards Rome had instigated war with the help of King Phraates V of Parthia.

To avoid a full-scale war with Rome, Phraates V soon ceased his support to the Armenian monarchs.

This led Tigranes IV and Erato to acknowledge Roman suzerainty[12] and send their good wishes and submission to Rome.

[14] In 1 C.E., Tigranes IV was killed in battle,[14] perhaps ending an internal Armenian revolt[15] of those who were infuriated by the royal couple becoming allies to Rome.

Ariobarzanes through his father was a distant relative of the Artaxiad dynasty as he was a descendant of a sister of King Artavasdes II.

[19][20] Tigranes V was accompanied by his grandfather Archelaus of Cappadocia and the future Roman emperor Tiberius to Armenia, where he was installed as king.