What was the main written language of the Sasanian Empire’s royal inscriptions?

Middle Persian was the main written language of the Sasanian Empire’s royal inscriptions. It was also called Pahlavi in many historical and scholarly contexts, although “Pahlavi” can refer more broadly to scripts and Middle Iranian languages.

Sasanian rulers used Middle Persian for inscriptions celebrating royal victories, religious foundations, and administrative authority. Important examples include the inscriptions of Shapur I at Naqsh-e Rostam and the trilingual inscription of Shapur at the Kaaba-ye Zartosht. These texts may appear alongside Greek or Parthian, reflecting the empire’s multilingual population and western political connections.

Middle Persian developed from earlier Iranian languages and later influenced New Persian. It was written in a form of the Aramaic-derived Pahlavi script, whose spelling can be difficult because it preserved historical spellings and used Aramaic-derived heterograms. Avestan, by contrast, was the sacred language of Zoroastrian scripture, not the ordinary language of Sasanian royal administration.