He was the son of King Ariobarzanes I of Cappadocia and his wife Queen Athenais Philostorgos I. Ariobarzanes II was half Persian and half Greek.
Ariobarzanes II married the princess Athenais Philostorgos II, one of the daughters of King Mithridates VI of Pontus.
He was an ineffective ruler, requiring the aid of Gabinius in 57 BC to ward off his enemies.
He was successful in maintaining rule over Cappadocia for approximately eight years before being assassinated by Parthian favorites.
[1] An inscription from the site reads: Those appointed by him for the construction of the Odeion, Gaius and Marcus Stallius, sons of Gaius and Menalippos, [set up the statue of] their benefactor King Ariobarzanes Philopator, son of King Ariobarzanes Philoromaios and Queen Athenais.