These men were responsible for providing for the needs of Solomon's large household, including his courtiers, and for his thousands of horses (v. 28). Two were Solomon's sons-in-law (vv. 11, 15). The district arrangement seems designed to move Israel away from tribal independence to cooperation under the new centralized government, though the district boundaries approximated the tribal boundaries.55
". . . this was a radical and decisive step, and that not only because it imposed upon the people an unprecedented burden. It meant that the old tribal system, already increasingly of vestigial significance, had been, as far as its political functioning was concerned, virtually abolished. In place of twelve tribes caring in turn for the central shrine were twelve districts taxed for the support of Solomon's court!"56
Note that Solomon did not include Judah and Jerusalem. This gave Judah a great advantage economically. Perhaps Solomon favored Judah because it was his tribe. This favoritism may have been a factor in the revolt of the northern tribes later (12:4).
Solomon's throne exercised four spheres of political influence. First, there was the homeland. This was the geographical area Joshua had assigned to the 12 tribes. In Solomon's day Israel occupied only this area. Second, there were adjacent provinces (i.e., Damascus, Ammon, Moab, Edom, et al.). Solomon taxed these and conscripted them for military service. They enjoyed protection and the benefits of Israel's central government. Third, there were the vassal states (i.e., Zobah, Hamath, Arabia, possibly Philistia, et al.) that Israel controlled. These enjoyed some autonomy such as native rulers and internal fiscal policies. They recognized Solomon's authority, however, provided some tribute, and pledged loyalty to him. Israel in return defended them from alien forces when necessary. Fourth, there were the allied states (i.e., Phoenicia, Egypt, et al.). These countries enjoyed equality with Israel. They defended each other as needed, traded with each other, and generally cooperated with one another.57
Clearly Solomon's kingdom had a large bureaucracy.