Kaleb, also known as Saint Elesbaan, was King of Aksum, situated in modern-day Eritrea and Northern Ethiopia. Kaleb invaded Yemen around 520, to overthrow Dhu Nuwas, a Jew who was persecuting the Christian community of Najran. After much fighting, Kaleb's soldiers eventually routed Yusuf's forces. They killed the king, allowing Kaleb to appoint Sumuafa' Ashawa', a native Christian (named Esimiphaios by Procopius), as his viceroy of Himyar.
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