C. F. Keil and Franz Delitzsch on 1 Kings 4:17

1Ki 4:17 Jehoshaphat the son of Paruach, in Issachar; i.e., over the whole of the territory of that tribe in the plain of Jezreel, with the exception of the cities of Taanach, Megiddo, and Bethshean, which were in the southern portion of it, and were allotted to the Manassites, and, according to 1Ki 4:12, were put under the care of Baanah; and not merely in the northern part of Issachar, “with the exception of the plain of Jezreel,” as Thenius erroneously maintains. Zebulun may possibly have also formed part of his district, if not entirely, yet in its southern portion, provided that the northern portion was assigned to Ahimaaz in Naphtali, since Zebulun had no prefect of its own.