Following the death of Alexander the Great in 323 BCE, the Macedonian's conquests were divided amongst the diadochi at the Partition of Babylon. The former Achaemenid satrapy of Media was divided into two states: The greater (southern) part -- 'Media Magna' -- was assigned to Peithon, one of Alexander's bodyguards. The smaller (northern) region -- which had been the sub-satrapy of Matiene under the Achaemenids -- became 'Media Atropatene', after Atropates, the former Achaemenid governor of all Media but who had by then become father-in-law of Perdiccas, regent of Alexander's designated successor.
Shortly thereafter, Atropates refused to pay allegiance to Seleucus, and made Media Atropatene an independent kingdom. It subsequently lost the 'Media' prefix in the name and came to be simply 'Atropatene', Greek ᾿Ατροπατήνη.
The dynasty Atropates founded would rule the kingdom for several centuries, first independently, then as vassals of the Arsacids (who called it 'Aturpatakan'), then briefly as vassals of the Kingdom of Armenia (who called it 'Atrpatakan'). It was eventually annexed by the Arsacids, who then lost it to the Sassanids, who again called it 'Aturpatakan'.
On Easter day 628, the Byzantine Emperor Heraclius captured Gazaca, the capital. The Arabs under the Rashidun took control of the area during the reign of Umar, at some time between 639 and 643. Atropatene formed a separate province of the early Islamic caliphate and was considered to have had strategic importance. Middle Iranian (i.e. Parthian and Middle Persian) 'Aturpatakan' became Adarbaygan, Adarbayjan, Azarbaijan, Azerbaijan.