Procopius calls him "Hellestheaeus," a variant of the Greek version of his regnal name, Ge'ez: እለ አጽብሐ, romanized: ʾƎllä ʾAṣbəḥa (Histories, 1.20).

At Aksum, in inscription RIE 191, his name is rendered in unvocalized Gə‘əz as klb ’l ’ṣbḥ wld tzn "Kaleb ʾElla ʾAṣbeḥa, son of Tazena".

[8] Procopius, John of Ephesus, and other contemporary historians recount Kaleb's invasion of Yemen around 520, against the Himyarite king Yūsuf As'ar Yath'ar, known as Dhu Nuwas, a Jewish convert who was persecuting the Christian community of Najran.

They killed the king, allowing Kaleb to appoint Sumyafa Ashwa, a native Christian (named Esimiphaios by Procopius), as his viceroy of Himyar.

As a result of his protection of the Christians, Kaleb is known as Saint Elesbaan after the sixteenth-century Cardinal Caesar Baronius added him to his edition of the Roman Martyrology despite his being a Miaphysite.

[12] Stuart Munro-Hay opines that by this expedition Axum overextended itself, and this final intervention across the Red Sea, "was Aksum's swan-song as a great power in the region.

[15] Ethiopian tradition states that Kaleb eventually abdicated his throne, gave his crown to the Church of the Holy Sepulchre at Jerusalem, and retired to a monastery.

[24] This angered Gebre Meskel, who wanted to go to war against Israel, but he was stopped by priests who told him to wait until they had asked his father who his preferred successor was.