Atropatene (originally known as "Atropatkan" [ اترپتکان ] and "Atorpatkan" ) was an ancient kingdom established and ruled under local ethnic Iranian dynasts first with "Darius" of Persia and later "Alexander" of Macedonia, starting in the 4th century BC and includes the territory of modern-day Iranian Azarbaijan and Iranian Kurdistan. Its capital was Gazaca. Atropatene also was the nominal ancestor of the name Azarbaijan.
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, became Media Atropatene under Atropates, the former Achaemenid governor of all Media, 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 known simply as Atropatene. The dynasty Atropates founded would rule the kingdom for several centuries, first independently, then as vassals of the Arsacids (who called it 'Aturpatakan'). It was eventually annexed by the Arsacids, who then lost it to the Sassanids, who again called it 'Aturpatakan'. At some time between 639 and 643 the Arabs under the Rashidun took control of the area during the reign of Umar. Atropatene formed a separate province of the early Islamic caliphate and was considered to have had strategic importance. It was during the Arab period that Middle Iranian (i.e. Parthian and Middle Persian) Aturpatakan became Adarbaygan, Adarbayjan, Azarbaijan,.