Shahrestaniha i Eranshahr

Šahrestānīhā ī Ērānšahr (literally the provincial capitals of Iran) is a surviving Middle Persian text on geography, which was completed in the late eighth or early ninth centuries AD. The text gives a numbered list of the cities of Eranshahr and their history and importance for Persian history. The text itself has indication that it was also redacted at the time of Khosrow II (r. 590–628) in 7th century as it mentions several places in Africa and Persian Gulf conquered by the Sasanians.

The book serves as a source for works on Middle Iranian languages, a source on Sasanian administrative geography and history, as well as a source of historical records concerning names of the Sasanian kings as the builder of the various cities. The text provide information on the Persian epic, the Xwadāy-nāmag (lit. “Book of Kings”).

The book may be the same as "Ayādgār ī Šahrīhā" (lit. “Memoir of Cities") named in the Bundahishn and said to have been written following an order of Kavadh I.

The terms Eranshahr () and Eran were in use in Sasanian Iran. From early Sasanian era (Ardashir I and Shapur I's elaborations), as a designation of their land they adopted Ērānšahr “Empire of the Iranians” and this served as the official name of their country.

Ardashir I, who was the first king of the Sasanian Empire, had used the older word ērān (Parthian aryān) as part of his titles and in accordance with its etymology. At Naqsh-e Rostam in Fars province and the issued coins of the same period, Ardashir I calls himself Ardašīr šāhānšāh ērān in the Middle Persian version and šāhānšāh aryān in its Parthian version both meaning “king of kings of the Aryans.” His son Shapur I referred to himself as šāhānšāh ērān and anērān (lit. "king of kings of the Aryans and the Non-Aryans") in Middle Persian and šāhānšāh aryān and anaryān in Parthian. Later kings used the same or similar phrases. and these titles became the standard designations of the Sasanian sovereigns.

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