Who is Iddo? 2 Chronicles 13:22

2 Chronicles 13:22 The other events of Abijahs reign, what he did and what he said, are written in the annotations of the prophet Iddo.

The Chronicler extensively used historical documents to give his readers a historical account about the past (1 Chron. 5:18; 2 Chron. 14:1, 9; 16:1, 12, 13). R. B. Dillard conveys:

Iddo is cited as a source under other "titles" (9:29; 12:15), but only here under the "Midrash" of the Prophet Iddo. The term "midrash" occurs only here and in 24:27; its precise connotations are not known. The term may mean simply annotations or commentary, or it may have already begun to develop in the direction of the sense it would have in later rabbinic exegesis. It is not implausible that a work showing features of later exegesis would have been available in the Chronicler's own day; the elaboration and commentary on Scripture which became known as midrash was already known by the period of the Qumran sect (Lemke, Synoptic Studies, 146). In the absence of fuller evidence surrounding the use of the term, one can only speculate. The Chronicler frequently introduces chronological notes not found in Kings into his account.

Reference