The most celebrated events of Caleb's reign took place not in Africa but in South Arabia, considered by the Ethiopians to be part of their empire. Christianity had become fairly widespread in Yemen but encountered strong opposition from the region's long-established Jewish community and from local nationalists. In 523 a fiercely anti-Ethiopian and anti-Byzantine Arab convert to Judaism, Yusuf Asar Dhu Nuwas, took power in the kingdom of Himyar. Whether Dhu Nuwas planned to establish an explicitly Jewish state is debatable -- many of his followers were pagan or Nestorian -- but most of his enemies were Christian, and his war to establish Himyar's full independence from Axum took on a distinctly religious character. Churches were burned and Arab Christian civilians were massacred, most famously at Nagran; Dhu Nuwas is said to have justified such atrocities by referring to the horrendous persecution of Jews in the Roman Empire.
Fighting an overseas war was difficult for Ethiopia, but outside help became available when news of the Nagran massacre reached the north. Patriarch Timothy of Alexandria wrote a letter to Caleb urging more aggressive action, and the Byzantine emperor Justin I offered the use of 60 ships. The ensuing campaign, which Caleb led in person, was in all respects a Crusade, under the spiritual guidance of the celebrated Axumite monk Pantaleon, who figures prominently in some of the many amazing legends which grew out of the war. The Ethiopian forces were eventually victorious in a great battle on the seashore at Zabid, where Dhu Nuwas himself died in the surf.
News of the Ethiopian emperor's rescue of the Christians of Himyar spread throughout the Orthodox world, and Caleb (who eventually abdicated his throne to become a monk, sending his gold crown to be kept near the Holy Sepulchre in Jerusalem) is venerated as a saint not only in the Ethiopian Church but also, as St. Ellasbaan (i.e. Ella Asbeha), by the Greek Orthodox and Roman Catholics. South Arabia, however, remained a restless province, and Caleb soon granted it de facto independence under the Christian prince Abraha. In 570, the year of Muhammad's birth, Abraha's army elephant corps attacked Mecca, giving that famous year the name "Year of the Elephant" in Arab history. Another Islamic echo of the wars of Caleb may be in Sura 85 of the Koran, which describes how those who burn the Saints burn themselves; this is thought by many commentators to refer to Dhu Nuwas and the Martyrs of Nagran.
Norman Hugh Redington