Aksumite invasions of Himyar

Aksum and Himyar faced each other across the southern Red Sea, and in the early 6th century their rivalry became bound up with religion and with the contest between Byzantium and Persia. The kings of Himyar had adopted a form of Judaism in the late 4th century, while Christianity spread among their subjects, above all at Najran. Around 518 Kaleb (Ella Asbeha) sent an army — commanded, according to the Syriac Book of the Himyarites, by one Hayyan — which placed a Christian Himyarite, Maʿdikarib Yaʿfur, on the throne and left an Aksumite garrison at Zafar, the capital. In 522 the Jewish noble Yusuf Asʾar Yathʾar, remembered in Arabic tradition as Dhu Nuwas, seized power, killed the Aksumites in Zafar, burned the church there, fortified the coast against a new landing and in 523 crushed Christian Najran.

The massacre outraged the Christian world. Urged on by Byzantium — the sources name the emperor Justin I, although by Hatke’s dating Justinian already reigned — Kaleb crossed the sea himself at the head of a large army. Yusuf was killed during the landing (Arabic tradition says that he rode his horse into the sea), and the Aksumites took Zafar, Sanaa, Marib and Najran. According to the historian George Hatke, Kaleb stayed in Arabia for seven months, restoring the churches, and set up a Christian Himyarite, Sumyafaʿ Ashwaʿ (Esimiphaios in Procopius), as a king paying tribute to Aksum. The date of the expedition is disputed: many works give 525, while Hatke (in his dictionary articles on Kaleb and on Aksum; in the one on Abraha he gives 525) and Iwona Gajda, specialists in the history of South Arabia, date it to about 529–530.

After the war Justinian sent the envoy Julianus to ask Kaleb and Sumyafaʿ Ashwaʿ to buy Indian silk for the Romans and to attack Persia, but neither did so. Nor did Aksumite control last: soldiers who had stayed behind in the fertile country deposed Sumyafaʿ Ashwaʿ and raised to power Abraha, a Christian who, according to Procopius, had been the slave of a Roman shipowner at Adulis. Of the two armies Kaleb sent against him, one went over to Abraha and the other was beaten, and Abraha later agreed to pay tribute to Kaleb’s successor; in all, Hatke counts no fewer than four invasions of South Arabia under Kaleb, one of which he led in person. The historian Stuart Munro-Hay called Kaleb’s great expedition Aksum’s “swan-song” as a great power in the region.