When Hurmazd II died, the Persian nobles were determined to show their power. None of his three sons was allowed to succeed (although one, another Hurmazd, escaped and fled to the Romans - more will be heard of him). Instead there was (allegedly) the most bizarre coronation of all time: Hurmazd II's unborn child was made king of kings while still in his mother's womb. The Magi had foretold he'd be a boy. The nobles assumed they would continue to hold the real power. But while Shapur was growing up, things had already started to go wrong for them.
Shapur II (probably.)
Shapur's very long reign was marked by very significant developments which in time would become major problems :
- The first serious confrontation with the Arabs;
- The Roman choice of Christianity as their official religion;
- The re-appearance in Iran of warlike nomads from the steppes to the north east.
While Shapur II was still a boy, the Arabs from the southern side of the Persian Gulf began a series of attacks across the gulf into Persia and Elymais, growing bolder and more aggressive as Shapur's regents did little to discourage them. They even planned an assault on Ctesiphon. Believing no one would stop them, they eventually decided they could colonise the northern coast of the Gulf. They were wrong. By now Shapur was old enough (aged 16 in AD 325) to take charge. The Savaran cavalry soon drove the Arab occupiers out of Persis and Elymais, and Shapur then led a counter-invasion of Bahrain and the Arabian coast. There was large-scale slaughter. Shapur's treatment of his prisoners was remembered by the Arabs as especially brutal - they called him "the shoulder-piercer", because he roped his captives together through their shoulders.
Head of a cavalry horse, 4th century AD. Found at Kerman, central Iran.
Many Arabs were transported to underpopulated areas of Sasanian territory, like Kerman or Khuzistan. Those who stayed in Arabia were pushed away from the coast, so that the entire coastline of the Persian Gulf came under Sasanian control. The Lakhmid dynasty of Arabs, who lived west of the Euphrates in southern Iraq were befriended by Shapur II to form a buffer against the other Arabs to the south (Bedouin) and west (Ghassanids), and the Romans. Thus Shapur II partly executed the strategy which the Sasanians could have adopted earlier if they'd supported Palmyra against the Romans.