The Shapur Ist equestrian investure rock relief, “Naqsh-e Rajab IV” was directly inspired by the former relief of Ardashir at Naqsh-e Rostam I. If the principe of symetry is kept, it shows slight differences with the model. Unlike Ardashir’s image, no dead ennemy is seen under the horses wrecks, the disposition of the king and the god is inversed, Ahuramazda being on the left side of the register while the king is on the right side, and no servant is shown behind the king. Unfortunatly, the face of the characters were destroyed by hammering, probably during later times.

On the artistic topic, the proportional dimensions of the characters and the horses are improved, coping more with reality. The impression of statism given by the scene is finely balanced by an aerial movement given to the scarfs, ribbons, and clothes. Such evolution could possibly sign a roman influence. The lack of ennemy suggest that such relief was executed just after Shapur’s access to the power, and before his first victorious campaign against the romans. The relief is facing another one of Shapur, Naqsh-e Rajab I.

forming with this last a kind of pictural corridor leading to Ardashir’s investiture relief of .Naqsh-e Rajab III.