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.

The Iranian soldiers and bureaucrats started intermarrying with the local population; their offspring became known as the al-Abna' ("the sons").

[2] It is uncertain whether they kept practicing Zoroastrianism, or had been influenced by the South Arabian paganism and the local Christianity.

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.

[3] The abna' retained their distinct identity during the Islamic period, but were gradually absorbed into the local population and thus disappeared from records.