As for the descendants of Levi, the family heads up to the days of Johanan son of Eliashib were recorded in the Book of the Chronicles.
We have here the names, and little more than the names, of a great many priests and Levites, that were eminent in their day among the returned Jews. Why this register should be here inserted by Nehemiah does not appear, perhaps to keep in remembrance those good men, that posterity might know to whom they were beholden, under God, for the happy revival and re-establishment of their religion among them.
Commenting on Nehemiah 12:1-26
And the chief of the Levites,.... Here the thread of the history of Nehemiah, interrupted by the insertion of the two preceding verses, is carried from the priests to the Levites in the times of the third high priest: Hashabiah, Sherebiah, and Jeshua the son of Kadmiel; these were singers, since it follows: with their brethren over against them, to praise and to give thanks...
SUCCESSION OF THE HIGH PRIESTS. (Neh. 12:10-47) Jeshua begat Joiakim, &c.--This enumeration was of great importance, not only as establishing their individual purity of descent, but because the chronology of the Jews was henceforth to be reckoned, not as formerly by the reigns of their kings, but by the successions of their high priests.
Commenting on Nehemiah 12:10-47