Kartir was a powerful and influential Zoroastrian priest during the reigns of four Sasanian kings in the 3rd century. His name is cited in the inscriptions of Shapur I and the Paikuli inscription of Narseh. Kartir also had inscriptions of his own made in the present-day Fars Province. His inscriptions narrates his rise to power throughout the reigns of Shapur I, Hormizd I, Bahram I, and Bahram II. During the brief reign of Bahram II's son and successor Bahram III, Kartir was amongst the nobles who supported the rebellion of Narseh, who overthrew Bahram III and ascended the throne. During Narseh's reign, Kartir faded into obscurity.

Shapur I was the second Sasanian King of Kings of Iran. The precise dating of his reign is disputed, but it is generally agreed that he ruled from 240 to 270, with his father Ardashir I as co-regent until the death of the latter in 242. During his co-regency, he helped his father with the conquest and destruction of the city of Hatra, whose fall was facilitated, according to Islamic tradition, by the actions of his future wife al-Nadirah. Shapur also consolidated and expanded the empire of Ardashir I, waged war against the Roman Empire, and seized its cities of Nisibis and Carrhae while he was advancing as far as Roman Syria. Although he was defeated at the Battle of Resaena in 243 by Roman emperor Gordian III, he was the following year able to win the Battle of Misiche and force the new Roman emperor Philip the Arab to sign a favorable peace treaty that was regarded by the Romans as "a most shameful treaty".