According to I Kgs 14:25 & II Chron 12:2 Shishak, the king of Egypt, invaded during Rehoboam's fifth year. That Rehoboam invested heavily in fortifications indicates that he may not have been surprised.>/p>
Shishak records his campaign in hieroglyphics on the wall of the Temple to Amun in Upper Egypt. The inscription includes a list of cartouche-enclosed names of 156 cities and towns in Israel and Syria which he claims to have subjugated, indicating his intentions were not focused Rehoboam and Judah since most of the cities listed were in the territory recently seceeded from the Davidic kingdom. These include Taanach, Shunem, Beth-shean, Rehob, Mahanaim, Gibeon, Beth-horon, Ajalon, Arad, and Megiddo.