Yemen was conquered in 570 by a small expeditionary
aswaran force led by the Sasanian veteran
Vahrez−the
Himyarite prince
Sayf ibn Dhi-Yazan was then appointed as a vassal king of the Sasanians in the country, whilst Vahrez went back to the Sasanian capital of
Ctesiphon. One of the main reasons behind the Sasanian conquest was due to their interest in dominating the trade route from
Constantinople to
India and the
Far East, which was now possible with their authority established in Yemen. However, in 575 or 578, Sayf was killed by the Ethiopians during an uprising, which forced Vahrez to return to Yemen with a force of 4,000 men, and expel the Ethiopians once again. He then installed Sayf's son Ma'di Karib as the new king of Yemen. A large Iranian garrison was this time established in Yemen, with Vahrez as its governor. The Iranian soldiers and bureaucrats started intermarrying with the local population; their offspring became known as the ''
al-Abna''' ("the sons"). It is uncertain whether they kept practicing
Zoroastrianism, or had been influenced by the
South Arabian paganism and the
local Christianity. According to
al-Tabari, Vahrez's successors were; his son Marzban; his grandson Binagar; his great-grandson Khurrah Khosrow; and then a certain
Badhan, who was unrelated to the family of Vahrez. After the overthrow and death of the last prominent Sasanian king (
shah)
Khosrow II in 628, the Iranian nobles of Yemen made an alliance with the
Islamic prophet Muhammad, and thus the country became part of the Islamic political structure. The abna' retained their distinct identity during the Islamic period, but were gradually absorbed into the local population and thus disappeared from records. Their
nisba was
al-Abnāwī. ==List of governors==