Artaxerxes appears to have died in A.D. 240. He was succeeded by his son Shahpuhri, or Sapor, the first Sassanian prince of that name. According to the Persian historians, the mother of Sapor was a daughter of the last Parthian king, Artabanus, whom Artaxerxes had taken to wife after his conquest of her father. But the facts known of Sapor throw doubt on this story, which has too many parallels in oriental romance to claim implicit credence. Nothing authentic has come down to us respecting Sapor during his father's lifetime, but from the moment that he mounted the throne we find him engaged in a series of wars, which show him to have been of a most active and energetic character. Armenia, which Artaxerxes had subjected, attempted, it would seem, to regain its independence at the commencement of the reign; but Sapor easily crushed the nascent insurrection, and the Armenians made no further effort to free themselves till several years after his death. Contemporaneously with this revolt in the mountain region of the North a danger showed itself in the plains country of the South, where Manizen, king of Hatra, or El Hadhr, not only declared himself independent, but assumed dominion over the entire tract between the Euphrates and the Tigris, the Jezireh of the Arabian geographers. The strength of Hatra was great, as had been proved by Trajan and Severus; its thick walls and valiant inhabitants would probably have defied every attempt of the Persian prince to make himself master of it by force. He, therefore, resorted to stratagem. Manizen had a daughter who cherished ambitious views. On obtaining a promise from Sapor that if she gave Hatra into his power he would make her his queen, this unnatural child turned against her father, betrayed him into Sapor's hands, and thus brought the war to an end. Sapor recovered his lost territory; but he did not fulfil his bargain. Instead of marrying the traitoress, he handed her over to an executioner, to receive the death that she had deserved, though scarcely at his hands.