Charles Ellicott Commentary 1 Kings 15:10

"And forty and one years reigned he in Jerusalem: and his mother`s name was Maacah the daughter of Abishalom." — 1 Kings 15:10 (ASV)

His mother’s name was Maachah. —Maachah was (see 1 Kings 15:2) the wife of Rehoboam, and, therefore, grandmother of Asa. She appears, however, still to have retained the place of “queen-mother,” to the exclusion of the real mother of the king.