Charles Ellicott Commentary 2 Chronicles 12:3

"with twelve hundred chariots, and threescore thousand horsemen. And the people were without number that came with him out of Egypt: the Lubim, the Sukkiim, and the Ethiopians." — 2 Chronicles 12:3 (ASV)

With twelve hundred chariots. —The short account in Kings says nothing of the numbers or constituents of the invading host. The totals here assigned are probably round numbers founded on a rough estimate. The cavalry are exactly fifty times as many as the chariots. Thenius finds the numbers “not in credible.”

The Lubims, the Sukkiims, and the Ethi-opians. —Rather, Lybians, Sukkîyans, and Cushites (without the definite article). These were “the people”— i.e., the footmen. The Lybians and Cushites are mentioned together as auxiliaries of Egypt in Nahum 3:9. (Compare to 2 Chronicles 16:8.) The Sukkîyans are unknown, but the Septuagint and Vulgate render Troglodytes, or cave-dwellers, meaning, it would seem, the Ethiopian Troglodytes of the mountains on the western shore of the Arabian Gulf. (Compare to sukkô, “his lair,”Psalms 10:9.)