And the kings that ruled in the land of Edom, before the children of Israel had a king were these:

And these are the kings who have reigned in the land of Edom before the reigning of a king over the sons of Israel.

And these are the kings who were ruling in the land of Edom before there was any king over the children of Israel.

Now before the sons of Israel had a king, the kings who ruled in the land of Edom were these:

Et isti sunt reges, qui regnaverunt in terra Edom, antequam regnaret rex super filios Israel.

These are the kings that reigned, etc We must keep in memory what we have said a little before, that reprobates are suddenly exalted, that they may immediately fall, like the herb upon the roofs, which is destitute of root, and has a hasty growth, but withers the more quickly. To the two sons of Isaac had been promised the honor that kings should spring from them. The Idumeans first began to reign, and thus the condition of Israel seemed to be inferior. But at length, lapse of time taught how much better it is, by creeping on the ground, to strike the roots deep, than to acquire an extravagant pre-eminence for a moment, which speedily vanishes away. There is, therefore, no reason why the faithful, who slowly pursue their way, should envy the quick children of this world, their rapid succession of delights; since the felicity which the Lord promises them is far more stable, as it is expressed in the psalm, "The children's children shall dwell there, and their inheritance shall be perpetual." (Psalm 102:28.)

Before there reigned any king over - Israel - I suppose all the verses, from Genesis 36:31-39 inclusive, have been transferred to this place from 1-Chronicles 1:43-50, as it is not likely they could have been written by Moses; and it is quite possible they might have been, at a very early period, written in the margin of an authentic copy, to make out the regal succession in Edom, prior to the consecration of Saul; which words being afterwards found in the margin of a valuable copy, from which others were transcribed, were supposed by the copyist to be a part of the text, which having been omitted by the mistake of the original writer, had been since added to make up the deficiency; on this conviction he would not hesitate to transcribe them consecutively in his copy. In most MSS. sentences and paragraphs have been left out by the copyists, which, when perceived, have been added in the margin, either by the original writer, or by some later hand. Now, as the margin was the ordinary place where glosses or explanatory notes were written, it is easy to conceive how the notes, as well as the parts of the original text found in the margin, might be all incorporated with the text by a future transcriber; and his MSS., being often copied, would of course multiply the copies with such additions, as we have much reason to believe has been the case. This appears very frequently in the Vulgate and Septuagint; and an English Bible now before me written some time in the fourteenth century, exhibits several proofs of this principle. See the preface to this work.
I know there is another way of accounting for those words on the ground of their being written originally by Moses; but to me it is not satisfactory. It is simply this: the word king should be considered as implying any kind of regular government, whether by chiefs, dukes, judges, etc., and therefore when Moses says these are the kings which reigned in Edom, before there was any king in Israel, he may be only understood as saying that these kings reigned among the Edomites before the family of Jacob had acquired any considerable power, or before the time in which his twelve sons had become the fathers of those numerous tribes, at the head of which, as king himself in Jeshurun, he now stood.
Esau, after his dukes, had eight kings, who reigned successively over their people, while Israel were in affliction in Egypt.

And these [are] the (g) kings that reigned in the land of Edom, before there reigned any king over the children of Israel.
(g) The wicked rise up suddenly to honour and perish as quickly: but the inheritance of the children of God continues forever, (Psalm 102:28).

And these are the kings that reigned in the land of Edom,.... In the land that was afterwards called the land of Edom; for this laud was not so called when these kings began to reign: for, according to Bishop Cumberland (f), and those that follow him (g), these were Horite kings, who, after their defeat by Chedorlaomer, Genesis 14:5; in order to secure themselves the better from such a calamity for the future, set up a kingdom, and which appears, by the following account, to be elective; and so Maimonides (h) observes, that not one of these kings were of Edom: and these were:
before there reigned any king over the children of Israel; and there being no kings over Israel until many years after the times of Moses, hence some have thought these words are inserted by some other writer after him; but there is no need to suppose that; for Moses knew, from foregoing prophecies and promises, that kings would arise out of them and reign over them, Genesis 17:6; and this he was so certain of, that he himself, by divine direction, gave laws and rules to the children of Israel respecting their future kings, Deuteronomy 17:14; besides Moses himself was king in Jeshurun or Israel, Deuteronomy 33:5, so that it is the same as if he had said, these are the kings that reigned in Edom, before this time.
(f) Orig. Gent. Antiq. p. 1-24. (g) Bedford in his Scripture Chronology, and the Authors of the Universal History. (h) Morch Nevochim, par. 3. c. 50. p. 510.

kings of Edom--The royal power was not built on the ruins of the dukedoms, but existed at the same time.

(Parallel, 1-Chronicles 1:43-50). The Kings in the Land of Edom: before the children of Israel had a king. It is to be observed in connection with the eight kings mentioned here, that whilst they follow one another, that is to say, one never comes to the throne till his predecessor is dead, yet the son never succeeds the father, but they all belong to different families and places, and in the case of the last the statement that "he died" is wanting. From this it is unquestionably obvious, that the sovereignty was elective; that the kings were chosen by the phylarchs; and, as Isaiah 34:12 also shows, that they lived or reigned contemporaneously with these. The contemporaneous existence of the Alluphim and the kings may also be inferred from Exodus 15:15 as compared with Numbers 20:14. Whilst it was with the king of Edom that Moses treated respecting the passage through the land, in the song of Moses it is the princes who tremble with fear on account of the miraculous passage through the Red Sea (cf. Ezekiel 32:29). Lastly, this is also supported by the fact, that the account of the seats of the phylarchs (Genesis 36:40-43) follows the list of the kings. This arrangement would have been thoroughly unsuitable if the monarchy had been founded upon the ruins of the phylarchs (vid., Hengstenberg, ut sup. pp. 238ff.). Of all the kings of Edom, not one is named elsewhere. It is true, the attempt has been made to identify the fourth, Hadad (Genesis 36:35), with the Edomite Hadad who rose up against Solomon (1-Kings 11:14); but without foundation. The contemporary of Solomon was of royal blood, but neither a king nor a pretender; our Hadad, on the contrary, was a king, but he was the son of an unknown Hadad of the town of Avith, and no relation to his predecessor Husham of the country of the Temanites. It is related of him that he smote Midian in the fields of Moab (Genesis 36:35); from which Hengstenberg (pp. 235-6) justly infers that this event cannot have been very remote from the Mosaic age, since we find the Midianites allied to the Moabites in Numbers 22; whereas afterwards, viz., in the time of Gideon, the Midianites vanished from history, and in Solomon's days the fields of Moab, being Israelitish territory, cannot have served as a field of battle for the Midianites and Moabites. - Of the tribe-cities of these kings only a few can be identified now. Bozrah, a noted city of the Edomites (Isaiah 34:6; Isaiah 43:1, etc.), is still to be traced in el Buseireh, a village with ruins in Jebal (Rob. Pal. ii. 571). - The land of the Temanite (Genesis 36:34) is a province in northern Idumaea, with a city, Teman, which has not yet been discovered; according to Jerome, quinque millibus from Petra. - Rehoboth of the river (Genesis 36:37) can neither be the Idumaean Robotha, nor er Ruheibeh in the wady running towards el Arish, but must be sought for on the Euphrates, say in Errachabi or Rachabeh, near the mouth of the Chaboras. Consequently Saul, who sprang from Rehoboth, was a foreigner. - Of the last king, Hadar (Genesis 36:39; not Hadad, as it is written in 1-Chronicles 1:50), the wife, the mother-in-law, and the mother are mentioned: his death is not mentioned here, but is added by the later chronicler (1-Chronicles 1:51). This can be explained easily enough from the simple fact, that at the time when the table was first drawn up, Hadad was still alive and seated upon the throne. In all probability, therefore, Hadad was the king of Edom, to whom Moses applied for permission to pass through the land (Numbers 20:14.).
(Note: If this be admitted; then, on the supposition that this list of kings contains all the previous kings of Edom, the introduction of monarchy among the Edomites can hardly have taken place more than 200 years before the exodus; and, in that case, none of the phylarchs named in Genesis 36:15-18 can have lived to see its establishment. For the list only reaches to the grandsons of Esau, none of whom are likely to have lived more than 100 or 150 years after Esau's death. It is true we do not know when Esau died; but 413 years elapsed between the death of Jacob and the exodus, and Joseph, who was born in the 91st years of Jacob's life, died 54 years afterwards, i.e., 359 years before the exodus. But Esau was married in his 40th year, 37 years before Jacob (Genesis 26:34), and had sons and daughters before his removal to Seir (Genesis 36:6). Unless, therefore, his sons and grandsons attained a most unusual age, or were married remarkably late in life, his grandsons can hardly have outlived Joseph more than 100 years. Now, if we fix their death at about 250 years before the exodus of Israel from Egypt, there remains from that point to the arrival of the Israelites at the land of Edom (Numbers 20:14) a period of 290 years; amply sufficient for the reigns of eight kings, even if the monarchy was not introduced till after the death of the last of the phylarchs mentioned in Genesis 36:15-18.)
At any rate the list is evidently a record relating to the Edomitish kings of a pre-Mosaic age. But if this is the case, the heading, "These are the kings that reigned in the land of Edom, before there reigned any king over the children of Israel," does not refer to the time when the monarchy was introduced into Israel under Saul, but was written with the promise in mind, that kings should come out of the loins of Jacob (Genesis 35:11, cf. Genesis 17:4.), and merely expresses the thought, that Edom became a kingdom at an earlier period than Israel. Such a thought was by no means inappropriate to the Mosaic age. For the idea, "that Israel was destined to grow into a kingdom with monarchs of his own family, was a hope handed down to the age of Moses, which the long residence in Egypt was well adapted to foster" (Del.).

By degrees the Edomites worked out the Horites, and got full possession of the country. They were ruled by kings who governed the whole country, and seem to have come to the throne by election, and not by lineal descent: these kings reigned in Edom before there reigned any king over the children of Israel - That is, before Moses's time, for he was king in Jeshurun. God had lately promised Jacob that kings shall come out of his loins: yet Esau's blood becomes royal long before any of Jacob's did. Probably it was a trial to the faith of Israel, to hear of the power of the kings of Edom, while they were bond - slaves in Egypt: but those that look for great things from God must be content to wait for them. God's time is the best time. They were afterward's governed by dukes again, here named, who, I suppose, ruled all at the same time in several places in the country. They set up this form of government, either in conformity to the Horites, who had used it, Genesis 36:29, or God's providence reduced them to it, as some conjecture, to correct them for their unkindness to Israel, in refusing them passage through their country, Numbers 20:18.