About Kust i Adurbadagan and the quadripartition of the Sasanian Empire

The author discusses the administrative structure of the late Sasanian Empire with a special focus on the quadripartition of the Empire and the northern quarter of Sasanian dominions, the Kust i Adurbadagan. To do so, he proposes a new reading of the final paragraphs of the Shahrestaniha i Eranshahr, comparing it with the Armenian Geography of Ananias of Shirak and with evidence deiving from our increased knowledge od Sasanian administrative glyptics. Finally, the author suggests a new definition of this area.