By 570, the subjugated Himyarite king Saif ibn Dhi Yazan sought to end Aksum's hegemony in the region and, after being rejected by the Byzantine Empire, turned to the Persians for military aid.

Subsequently, the Persian army entered South Arabia and secured decisive victories in the Battle of Hadhramaut and then in the Siege of Sanaa, following which the Aksumites were largely expelled from the Arabian Peninsula, excluding Najran.

Around 520 AD, Kaleb of Aksum sent a military expedition to Yemen to fight against Dhu Nuwas, a Jewish ruler of the Himyarite Kingdom who had gained notoriety for his ongoing persecution of the Christian community in Najran.

[1][2] Following the successful Aksumite invasion, Dhu Nuwas was deposed and executed, and Kaleb appointed a Christian Himyarite native, Sumūyafa Ashwa, as his viceroy.

[2] In response to Maʽd-Karib's request, Khosrow I sent the Sasanian military general Wahrez and his son Nawzadh to Aksumite-ruled Yemen at the head of a small expeditionary force of 800 Dailamite cavalrymen in 570 CE.

The Persians sailed from the port of Obolla, seized the Bahrain Islands, and subsequently moved on Sohar, the portside capital of historical Oman; they then captured Dhofar and the remainder of Hadhramaut before landing at Aden.