Tirzah - This place, the capital of Jeroboam and his successors until the clays of Omri (1-Kings 14:17; 1-Kings 15:21, etc.), is identified by some with "Tulluzah", a town 3 miles northeast of Nablous, (by others with Teiasir).

King of Tirzah - This city appears to have been for a long time the capital of the kingdom of Israel, and the residence of its kings. See 1-Kings 14:17; 1-Kings 15:21, 1-Kings 15:33. Its situation cannot be exactly ascertained; but it is supposed to have been situated on a mountain about three leagues south of Samaria.
All the kings thirty and one - The Septuagint say εικοσι εννεα, twenty-nine, and yet set down but twenty-eight, as they confound or omit the kings of Beth-el, Lasharon, and Madon.
So many kings in so small a territory, shows that their kingdoms must have been very small indeed. The kings of Beth-el and Ai had but about 12,000 subjects in the whole; but in ancient times all kings had very small territories. Every village or town had its chief; and this chief was independent of his neighbors, and exercised regal power in his own district. In reading all ancient histories, as well as the Bible, this circumstance must be kept constantly in view; for we ought to consider that in those times both kings and kingdoms were but a faint resemblance of those now.
Great Britain, in ancient times, was divided into many kingdoms: in the time of the Saxons it was divided into seven, hence called the Saxon heptarchy. But when Julius Caesar first entered this island, he found four kings in Kent alone; Cingetorix, Carnilius, Taximagulus, and Segonax. Hence we need not wonder at the numbers we read of in the land of Canaan. Ancient Gaul was thus divided; and the great number of sovereign princes, secular bishops, landgraves, dukes, etc., etc., in Germany, are the modern remains of those ancient divisions.

The king of Tirzah, one,.... To what tribe this place fell is nowhere said: Adrichomius (u) places it in the tribe of Manasseh; and so does Bunting (w), who says of it, that it was a fair and beautiful city, situated on a high and pleasant mountain, in the tribe of Manasseh, twenty four miles from Jerusalem to the north: here Jeroboam had his royal seat, and so his successors unto Omri, 1-Kings 14:17; and Dr Lightfoot (x) seems to suspect as if Shechem in Mount Ephraim and Tirzah were the same; for, he says, if Shechem and Tirzah were not one and the same town, it appears that Jeroboam had removed his court, when his son died, from where it was when he first erected his idols; compare 1-Kings 12:25, with 1-Kings 14:17; and so it may argue that there was some space between: it was, no doubt, a very pleasant and beautiful city, as not only appears from its name, but from the allusion to it in Song 6:4,
all the kings thirty and one: it may seem strange that, in so small a country as Canaan was, there should be so many kings in it, since the length of it from Daniel to Beersheba was scarce an hundred sixty miles, as Jerom (y) says; who further observes, that he was ashamed to give the breadth of it, lest it should give occasion to Heathens to blaspheme; for, adds he, from Joppa to our little village Bethlehem (where they then were) were forty six miles, to which succeeded only a vast desert: but it may be observed, that in ancient times, in other countries, there were a great many kings, as here in Britain, and in France, Spain, and Germany, as Bishop Patrick has observed from several writers; and Strabo (z) testifies the same of the cities of Phoenicia or Canaan, that they had each of them separate kings, as Joshua here describes them.
(u) Theatrum Terrae Sanct. p. 74. (w) Travels, &c. p. 160. (x) Works, vol. 1. p. 78. (y) Epist. Dardano, tom. 3. p. 22. I. K. (z) Geograph. l. 16. p. 519.

Thirty one - Each being king only of one city or small province belonging to it, which was by the wise and singular providence of God, that they might be more easily conquered. But what a fruitful land must Canaan then be, which could subsist so many kingdoms! And yet at this day it is one of the most barren and despicable countries in the world. Such is the effect of the curse it lies under, since its inhabitants rejected the Lord of glory!