Though the exact birth-date of Ariobarzanes is unknown, it is speculated that he was born around 368 BC. His sister was the ancient Persian noblewoman and warrior Youtab. Ariobarzanes was made satrap of Persis (the southern province of Fars in present-day Iran) in 335 BC by Darius III Codomannus. Historians are surprised that Darius III appointed a satrap for Persepolis and Persis; apparently that office did not previously exist. Ariobarzanes commanded part of the Persian Army fighting against the Macedonians at the Battle of Gaugamela in 331 BC.
Following the Persian defeat at Gaugamela, Darius III realized he could not defend his capital Persepolis and travelled east to rebuild his armies, leaving Ariobarzanes in command. Meanwhile, Alexander the Great split his army and led his 14,000-strong force towards the Persian capital via the Persian Gates. There Ariobarzanes successfully ambushed Alexander the Great’s army, inflicting heavy casualties. The Persian success at the Battle of the Persian Gate was short lived though; after being held off for 30 days, Alexander the Great outflanked and destroyed the defenders. Some sources indicate that the Persians were betrayed by a captured tribal chief who showed the Macedonians an alternate path that allowed them to outflank Ariobarzanes in a reversal of Thermopylae. Ariobarzanes himself was killed either during the battle or during the retreat to Persepolis. Afterwards, Alexander continued towards Persepolis, seizing the city and its treasury, and eventually looting the city months after its fall.
Alexander the Great replaced him with Phrasaortes as Hellenistic satrap of Persis.