Adurbadagan (Middle Persian: Ādurbādagān/Āδarbāyagān, Parthian: Āturpātākān) was a northwestern province in the Sasanian Empire, corresponding almost entirely to the present-day Azerbaijan region in Iran.

According to the 9th-century Persian geographer Ibn Khordadbeh, the following cities were part of the province; Ardabil, Bagavan, Balwankirgh, Barza, Barzand, Ghabrawan, Ganzak, Khuy, Kulsarah, Maragha, Marand, Muqan, Shapurkhwast, Sisar, T'awrezh, Nariz, Urmia, Salmas, Shiz, and Warthan (Vardanakert), which he considered the northmost point of Adurbadagan.

[7][8] When the Arsacid house of Armenia was abolished and the country was made a Sassanian province in 428, the Armenian districts of Parskahayk and Paytakaran were incorporated into Adurbadagan.

[10] Since c. 323 BC the area of Adurbadagan had been ruled by local dynasties, initially by Atropates and his descendants, and a branch of the Parthian Arsacids from the 1st-century AD.

[12] The Iranologist Touraj Daryaee argues that the reign of the Parthian monarch Vologases V (r. 191–208) was "the turning point in Arsacid history, in that the dynasty lost much of its prestige.

"[13] The people of Adurbadagan (both nobility and peasantry) allied themselves with the Persian Sasanian prince Ardashir I (r. 224–242) during his wars against Vologases V's son and second successor Artabanus IV (r. 216–224).

[15] Under Kavad I (r. 488–496, 498–531) and his son and successor Khosrow I (r. 531–579) the empire was divided into four frontier regions (kust in Middle Persian), with a military commander (spahbed) in charge of each district.

However, not long after the battle, Khosrow II's maternal uncle Vistahm rebelled (precise date unknown, 590/1–596 or 594/5–600), and managed to gain control of some parts of Adurbadagan.

[24] The apocalyptical Middle Persian text Zand-i Wahman yasn may report some form of contemporary memory of the destruction of the temple; "They will remove Adur Gushnasp from its place .

The majority of the population in Adurbadagan were Western-Iranian ethnic groups who practised Zoroastrianism,[8] and spoke Adhari (including its dialect Tati).