The conquest of Yemen by Sasanid king Khusraw I Anushirwan (531 — 579) resulted in South Arabia becoming a territory under the Sasanid power. Initially, a model of indirect rule involving the administration by a local ruler, a vassal of the Sasanids, was applied, as was the case in some other regions, e.g., in al-Ḥīra. That ruler was a member of the noble family of Yazˀan, who appears in the sources under the name of Sayf or Maˁdīkarib. Although he had initiated the conquest of Yemen, the Sasanid general, in compliance with Khusraw’s instructions, vested him with power only after becoming sure that his enthronement would be agreed to by Yemenite aristocracy. Yazˀan ruled under a title sounding like ḥimyarān-shāh (King of the Ḥimyarites). Following Khusraw’s example, Yazˀan made a register of South Arabian noblemen and chieftains of vassal Arabic tribes, which identified the place of each nobleman in social hierarchy. Yazˀan’s relationship with other Arabic tribes was based upon agreements the contents of which varied from case to case. Yazˀan’s rule lasted for about 4 years, from the beginning of 572 till the beginning of 576 when he was assassinated. Then Khusraw, distrusting the Yazˀan family’s ability to rule over Yemen, appointed an Iranian governor.