I came across a study on the King of the North by Donn W. Leatherman of Southern called "Adventist University Adventist Interpretation of Daniel 10-12: A Diagnosis and Prescription". Its very good on how Adventist have been struggling with this issue, here is what he writes:
"The “king of the south” is understood to refer to the nation of Egypt. The “king of the north” was whatever power controlled the area north of Palestine, which, by the end of Daniel 11, was understood to be the Ottoman Empire. These interpreters expected the culmination of human history and the return of Christ to occur when Turkey, having failed in its attempts to reestablish control over Egypt, and beset by enemies from the North and East (possibly Russia and Persia), removed its capital from Istanbul to Jerusalem.
Foremost among the exponents of this interpretation wasUriah Smith, whose Thoughts Critical and Practical on the Book of Daniel, published in 1881, had extensive influence on subsequent generations of Adventists. Later editions of his works, which combined his book on Daniel with a similar volume on the Revelation, are less specific regarding the interpretation of the latter part of Daniel 11. This is particularly true of the editions printed after Smith's death. These later editions state that “the prophecy of verse 45 centers in that power known as the king of the north. It is the power that shall hold the territory possessed originally by the king of the north.”2 Clearly, after the demise of the Ottoman Empire, Smith's original interpretation seemed dubious.
Another Adventist, who had adopted views similar to those of Smith, was Stephen N. Haskell,3 the popularity of whose volume on Daniel rivaled that of Smith's work for some time after its publication in 1901. Other Adventist books expressing similar views include those of J. Grant Lamson (1909),4 Max Hill (1915),5 and O. A. Johnson (1919).6 One might have expected this interpretive tradition, especially the parts involving Turkey, to have died with the Ottoman Empire, but it persisted in the anonymous Two Great Prophecies (1925),7 and the works of M. H. Brown (1926)8 and W. H. Wakeham (1930),9 and even after
the Second World War in the works of E. A. Nixon (1945)10 and Walter E. Straw (1947).11 Without attempting to exegete the book of Daniel, other Adventist writers from this era reflected similar views in their works. These include Alonzo T. Jones (1900)12 and Arthur G. Daniels (1917).
After World War II many interpreters adopted a more radical revision of the earlier position represented by Uriah Smith, Stephen Haskell, and the great majority of Adventist writers of the early twentieth century. Beginning with Edwin R. Thiele,19 some Adventists identified Rome not only in verses 14 through 35, but in the last 10 verses of the chapter as well. Thiele's explanations of the last 6 verses of the chapter are somewhat vague historically, but nevertheless apply this passage to the papacy without hesitation.20 Thiele also differs from earlier interpreters in applying vss. 29-30 to the Crusades and the medieval church, rather than to the sack of Rome by the barbarian kingdoms.21 Thus Thiele's interpretation of Daniel 11:29-45 has a somewhat later historical framework and omits reference to the French revolution and to the Ottoman Empire. A similar position was adopted by Louis Were in 1949.22 Were makes no attempt to exegete the entire chapter; his focus is more narrow, but he does assert that the references to literal (i.e., pagan) Rome end in Daniel 11:30, and that vss.31-45 describe spiritual Rome.23 References to the “king of the north” in this part of the prophecy point to the papacy:
The power brought to view in Dan. 11:40-45 must be one whose activities concern the people of God—such has been Daniel's previouspresentations of the work of the papacy.24
In a 1955 publication, George McCready Price returned to the essential position of Uriah Smith regarding the interpretation of Daniel 11:29-32, but accepted the views of later interpreters who applied vss. 36-39 to the papacy. Price denies emphatically that these verses can be made to refer to revolutionary France.25 Furthermore, the last six verses of the chapter are also held to describe the demise of the papacy. Egypt, the king of the south, represents atheistic science. Price acknowledges two possible scenarios: one in which there are two major actors (the “king of the north” and the “king of the south”) and another in which there are three major actors, with the third person pronouns of verses 40 to 45 refer to some other entity. The differences between these interpretations Price holds to be slight, since “both views agree in saying that the main world power dealt with here is the Roman papacy, . . .”26
The last three verses of the chapter receive only brief comments. Price denies that the geographic references should be literally understood, states that parts of the passage are yet unfulfilled, and encourages the reader to wait until these passages are clarified by unfolding events before insisting on a specific interpretation.27
Robert Brinsmead (1960) concurs in the identification of the “king of the north” with the papal system and the “king of the south” with atheism.28 He sees in the final verses of Daniel 11 a conflict between two opposing ideologies —Babylonian and Egyptian. . . . Babylonian is to profess to be a Christian, to have a form of godliness, but to deny the power thereof. Egyptian is to repudiate the Christian religion and to deny the very existence of God.29 Clearly, the major focus of the closing verses of Daniel 11 in this interpretation is still on the demise of the papacy.
The Seventh-day Adventist Bible Commentary declines to speak decisively on this passage. In verse after verse the reader is presented with tentative speculation (“Some see specific reference here . . .”) or alternative and mutually contradictory views (“Others suggest . . .”).30 The editors suggest two possible interpretations of verse 40: that the “king of the north” is Turkey, and that the “king of the north” is the papacy.31 No comment is offered on vss. 41-44, and the comment on vs. 45 consists primarily of a warning from James White to be cautious in offering interpretations of unfulfilled prophecy.32
The view that the “king of the north” represents the papacy and that the final portion of Daniel 11 describes the eschatological demise of papal power is also supported (though with important differences in interpretation) by both Desmond Ford (1978) and Mervyn Maxwell (1981). Ford applies Daniel 11:29,30 to the evacuation of Antiochus IV from Egypt at the command of the Roman Senate. In subsequent passages he sees intimations of both the Antiochene desecration of the Jerusalem temple and the anti-Jewish and anti-Christian activities of Rome. Thus Ford holds the possibility for multiple fulfillmentsof these passages...Ford applies vss. 36-39 to the papacy, but is reluctant to be very specific on vss. 40-45. He remarks that at this point “we . . . enter upon delicate ground, as this is obviously in the realm of unfulfilled prophecy.” He does insist (against Price and Bunch) that there are only two powers, not three, in the conflict describedin these verses.34 He associates the “king of the south” with atheism, or “some latter-day movement opposed to religion.”35
Maxwell, whose interpretations are significantly closer to Adventist tradition, associates all of Daniel 11:29-45 with the papacy, specifically identifying the last six verses of the chapter with the “demise of Roman Christianity.”36 Nevertheless, he is considerably less specific in his interpretation of this passage than in his treatment of earlier chapters, or even of earlier parts of this chapter. He gives a detailed verse-by-verse interpretation of Daniel 11: 1-16. His comments on subsequent verses are more general, and are not always in canonical
order.37...."Adventist Interpretation of Daniel 10-12: A Diagnosis and Prescription https://digitalcommons.andrews.edu/jats/vol7/iss1/7
I found the above book by Louis F Were also. He is hitting the mark, and I like what he has in the beginning..
"Concerning the interpretation of Daniel’s previous prophecies Seventh-day Adventists are united.,But the same unity is not maintained concerning the interpretation of Daniel’s last prophecy – the reason for this is because the concluding portion of Daniel 11 (vs. 36-45) is not interpreted according to the same principle by which the previous parts are interpreted. When God’s people apply this principle consistently, the unity manifested concerning the earlier prophecies of Daniel will also exist in regard to this last prophecy. When this time comes as it surely will – there will be seen among us “a great revival,” that “great revival” which the Lord’s servant declares will come “when the books of Daniel and Revelation” are “better understood.” Testimonies to Ministers, p. 113."
So what caused the disunity on the King of the North in the church. Well I found more history on the Adventist view which shows where it deviated and was not "interpreted according to the same principle by which the previous parts are interpreted.":
"History of the Church’s Teaching on the King of the North.
Three Main Periods
1. 1846-1871 The King of the North said to be the Papacy.
There was general agreement on this during this time. James White and Uriah Smith both taught it. Uriah Smith applied Daniel 11:45 to the Papacy. See his editorial in the Review and Herald May 13, 1862 under the title, “Will the Pope Remove the Papal seat to Jerusalem?
2. 1871-1952. The King of the North said to be Turkey.
Around the beginning of this period Uriah Smith changed his views and began to teach that Daniel 11:36-39 Spoke about Revolutionary France, and that verses 40-45 dealt with Turkey. He wrote up these views in his book “Thoughts on Daniel and the Revelation”, published by the Review and Herald Publishing House of which he was the editor on and off for many years.
James White who was also editor of the Publishing House at times advised caution.
In 1877 war broke out between Turkey and Russia, and Smith preached on the “Eastern Question” at a camp meeting attended by the Whites, and there the two men clashed publicly over the issue. In November 15, 1877 an editorial by James White appeared. It was reprinted in the Review and Herald 27 November, 1877, urging caution. Uriah Smith did not heed James White’s appeal, and in the Review and Herald of June 6, 1878 (page 180) he wrote. “…we have reached the preliminary movements of the battle of Armageddon”. http://bereanbiblecorner.com/2014/03/05/the-king-of-the-north/
Reasons why Uriah Smith changed his views. See Ministry Magazine, March 1954
1. In 1798 the Pope was taken prisoner by the French general Berthier, and he died in exile in France. In 1870 the Pope lost all temporal power, after Garibaldi took away the Papal States and united Italy.
2.Secular opinion held that the Papacy would never recover. It seems strange to us now that Smith would go along with this idea since Rev. 13:3 says “the deadly wound was healed and all the world wondered after the beast”.
3.Introducing France, Turkey and Egypt into Daniel 11, made the prophecies seem to be current to people of those times, and thus more interesting and urgent. Smith did what so many others have done, and that is to try to interpret the prophecies by looking at the newspaper headlines of the day. The danger of doing this is that he forgot that prophecy was not given to us to make us wise about political event, but to let us know what is going to happen to God’s church.
4.At that time Russia seemed ready to close in on Constantinople (now called Istanbul), Smith thought that this move could well lead Turkey to move its capital to Jerusalem.
5.Bishop Newton and Adam Clarke and others had linked Daniel 11:40-45 to the Ottoman Empire.
6.Many scholars of the day also taught that Rev. 9 spoke about the Ottoman Empire and that Rev. 11 dealt with the French Revolution. Thus it was thought that these two chapters were parallel prophecies to those in Dan. 11:36-45.
Reasons why Smith’s views became dominate.
a. James White withdrew from the controversy for the sake of peace. See Ministry Magazine Nov. 1967, and Counsels to Writers and Editors,pp.76-77.
b. White did not spell out his views as clearly as did Smith.
c. Smith wrote his views into a book, – “Thoughts on Daniel and Revelation,” which out-lasted any thing White wrote in a magazine.
d. White died in 1881, while Smith served as editor of the Review and Herald for another eight years after White’s death. Thus Smith’s views became the dominate interpretation until about 1952.
3. 1952 to the Present. The King of the North again said to be the Papacy.
Reasons for the Return to the Earlier Position. See Ministry Magazine March 1954, p 24.
“ Not until the events so confidently predicted did not materialize, and the Papacy, instead of having ‘fallen to rise no more,’ again became a decisive influence in international affairs with a resumption of temporal power in 1929, did our Bible students undertake a re-examination of our denominational interpretations of these prophecies.” (Note that this quotation is dealing specifically with Dan. 11:36-39, but that which it states is also true about the King of the North as being the Papacy.)
This is from another SDA forum...
When it was first brought forth by some that the "King of the North" (KON) was somehow shifted from Rome unto Turkey, James White, a trusted leader in the church knew the KON was indeed Rome, and Uriah Smith, another trusted leader in the church at the time was claiming on a pulpit before the people that the KON was Turkey for some odd reason. He (James) then openly rebuked Uriah before the people to try and prevent confusion being cultivated in the church, and contrary to some that claim otherwise, that act of rebuke is what upset Ellen White enough to make the statement shared below. You will notice that she didn’t disagree with James at all on the KON as some assume and hope to build on by avoiding some basic facts that confirm otherwise. She did however disagree with how he (James) rebuked Smith before the people. It clearly says this in SOP…
•“My husband had some ideas on some points differing from the views taken by his brethren. I was shown that however true his views were, God did not call for him to put them in front before his brethren and create differences of ideas...
Speculative ideas should not be agitated, for there are peculiar minds that love to get some point that others do not accept, and argue and attract everything to that one point, urging that point, magnifying that point, when it is really a matter that is not of vital importance and will be understood differently. Twice I have been shown that everything of a character to cause our ministers to be diverted from the very points now essential for this time should be kept in the background.” -Christ Triumphant 330.3,4
The above is echoed in The Prophetic Faith of Our Fathers, vol. 4, Page 1067
•The year following White repeats his position at the General Conference of 1878 and, following his impressive succession of “if’s,” comes to certain emphatic conclusions. Differing from Smith’s later views on the latter part of Daniel 11, he found a distinct parallel between this chapter and Daniel 2, 7, and 8. White’s position in 1877 and his line of reasoning are as follows:
“Let us take a brief view of the line of prophecy four times spanned in the book of Daniel. It will be admitted that the same ground is passed over in chapters two, seven, eight, and eleven, with this exception that Babylon is left out of chapters eight and eleven. We first pass down the great image of chapter two, where Babylon, Persia, Greece, and Rome are represented by the gold, the silver, the brass, and the iron. All agree that these feet are not Turkish but Roman. And as we pass down, the lion, the bear, the leopard, and the beast with ten horns, representing the same as the great image, again all will agree that it is not Turkey that is cast into the burning flame, but the Roman beast. So of chapter eight, all agree that the little horn that stood up against the Prince of princes is not Turkey but Rome. In all these three lines thus far Rome is the last form of government mentioned.
“Now comes the point in the argument upon which very much depends. Does the eleventh chapter of the prophecy of Daniel cover the ground measured by chapters two, seven, and eight? If so, then the last power mentioned in that chapter is Rome.”
And again, in a General Conference session sermon almost a year later, he said:
“There is a line of historic prophecy in chapter eleven, where the symbols are thrown off, beginning with the kings of Persia, and reaching down past Grecia and Rome, to the time when that power ‘shall come to his end, and none shall help him.’ If the feet and ten toes of the metallic image are Roman, if the beast with ten horns that was given to the burning flames of the great day be the Roman beast, if the little horn which stood up against the Prince of princes be Rome, and if the same field and distance are covered by these four prophetic chains, then the last power of the eleventh chapter, which is to ‘come to his end and none shall help him,’ is Rome. But if this be Turkey, as some teach, then the toes of the image of the second chapter are Turkish, the beast with ten horns of the seventh chapter represents Turkey, and it was Turkey that stood up against the Prince of princes of the eighth chapter of Daniel. True, Turkey is bad enough off; but its waning power and its end is the subject of the prophecy of John and not of Daniel.” (From sermon on Sabbath preceding General Conference session.) -The Prophetic Faith of Our Fathers, vol. 4, Page 1067. 1-5
Notice that after James White made this biblical statement regarding the KON that you will not find any statement made by Ellen White correcting or even rebuking him on this prophetic and historic fact once published for all to read at their leisure. This not only confirms the KON is preached and taught to be Rome by James and Ellen White, it also confirms Ellen White never rebuked James White for declaring this truth as a rebuke against Uriah Smith that day as some twist out of context to this day. Her rebuke to her husband was clearly and solely based on the method by which James rebuked Uriah.
Now here is a really good study that really makes sense and shows how it gets to the Papacy, with a breakdown of Daniel 11 on what the verses give us:
"Daniel 11:1 King James Version (KJV)
"1 Also I in the first year of Darius the Mede, even I, stood to confirm and to strengthen him."
'The language of Daniel 11-12 is not symbolic in the same way that it is in chapters 2, 7 and 8. There are no images, beasts, or horns. Just the same, its language is cryptic, almost like a code. Each sentence condenses quantities of information, and many metaphors are employed.
These qualities have led to a variety of interpretations. There are, however, two very useful guidelines that all interpretations must follow to be acceptable:
1. This vision begins with a reference to King Cyrus and ends with God’s people delivered. So just like the other prophecies of Daniel, this one does not focus in on a narrow span of history but covers a long time span from the prophet’s day to the end of the world. This also means there should be some parallels that can be identified between this vision and the previous ones.
2. Within the text are several specific phrases that can be accurately pinned to certain historical events or time periods.
Then it goes through the verse:
Daniel 11:2 King James Version (KJV)
"2 And now will I shew thee the truth. Behold, there shall stand up yet three kings in Persia; and the fourth shall be far richer than they all: and by his strength through his riches he shall stir up all against the realm of Grecia."
The “fourth” king of Persia after Cyrus was Xerxes (Greek name for Ahasuerus), the husband of Queen Esther, who ruled at the height of Persian power and wealth. He raised a huge army with contingents from forty different nations and attacked Greece around 480 BC.
The Persian invasion was eventually repelled, but it roused a burning desire on the part of the independent city states of Greece to unite and average themselves on the Persians. There is much more detail on the rulers and activities of this kingdom than we have seen in previous visions.
Daniel 11:3-4 King James Version (KJV)
"3 And a mighty king shall stand up, that shall rule with great dominion, and do according to his will.4 And when he shall stand up, his kingdom shall be broken, and shall be divided toward the four winds of heaven; and not to his posterity, nor according to his dominion which he ruled: for his kingdom shall be plucked up, even for others beside those."
These two verses deal with Alexander’s conquests and the subsequent four divisions of his kingdom. This is the end of the obvious and easy sections of this prophecy.
Now comes Daniel 11:5-15 which is a bit long so I will just put the interpretation:
"These verses deal with the intricate details of the rulers and activities of the divided kingdom of Greece. Ultimately two of these divisions came to dominate to such an extent that the Bible record accurately portrays them under the titles of “The King of the North,” and “The King of the South.”
The enemies of Israel, such as Babylon and Egypt, always attacked from the north and the south. Thus “The King of the North” and “The King of the South” came to symbolize the adversaries of God’s people. This entire vision depicts these enemies as warring powers whose battles adversely affect God’s people."
Then we get to Rome:
"Daniel 11:16-20 King James Version (KJV)
"16 But he that cometh against him shall do according to his own will, and none shall stand before him: and he shall stand in the glorious land, which by his hand shall be consumed.
17 He shall also set his face to enter with the strength of his whole kingdom, and upright ones with him; thus shall he do: and he shall give him the daughter of women, corrupting her: but she shall not stand on his side, neither be for him.
18 After this shall he turn his face unto the isles, and shall take many: but a prince for his own behalf shall cause the reproach offered by him to cease; without his own reproach he shall cause it to turn upon him.
19 Then he shall turn his face toward the fort of his own land: but he shall stumble and fall, and not be found.
20 Then shall stand up in his estate a raiser of taxes in the glory of the kingdom: but within few days he shall be destroyed, neither in anger, nor in battle."
This section applies to the Pagan Roman Empire; it is the “King of the North” that “none shall stand before.” In 63 BC the Roman General Pompey interceded in a Jewish civil war and declared Judea a Roman protectorate.
Verses 17-19 are generally applied to Julius Caesar, ending with his assassination. Caesar Augustus, who, at the time of Christ’s birth, decreed that “the entire world should be taxed” (Luke 2:1), is pointed out in verse 20"
Then we get to what happens after Rome:
"Daniel 11:21-24 King James Version (KJV)
"21 And in his estate shall stand up a vile person, to whom they shall not give the honour of the kingdom: but he shall come in peaceably, and obtain the kingdom by flatteries.
22 And with the arms of a flood shall they be overflown from before him, and shall be broken; yea, also the prince of the covenant.
23 And after the league made with him he shall work deceitfully: for he shall come up, and shall become strong with a small people.
24 He shall enter peaceably even upon the fattest places of the province; and he shall do that which his fathers have not done, nor his fathers' fathers; he shall scatter among them the prey, and spoil, and riches: yea, and he shall forecast his devices against the strong holds, even for a time."
Here is where it starts to get harder, but if you look at the other prophecies in Daniel, the power that arises after Pagan Rome is the Papacy. So we go over how this comes to bear.." prophecy here shifts over to Papal Rome, with verse 22 referring to the papacy setting itself up against Christ, corresponding to “magnified himself even to the prince of the host” in Daniel 8:11."
Daniel 11:25-30 King James Version (KJV)
"25 And he shall stir up his power and his courage against the king of the south with a great army; and the king of the south shall be stirred up to battle with a very great and mighty army; but he shall not stand: for they shall forecast devices against him.
26 Yea, they that feed of the portion of his meat shall destroy him, and his army shall overflow: and many shall fall down slain.
27 And both of these kings' hearts shall be to do mischief, and they shall speak lies at one table; but it shall not prosper: for yet the end shall be at the time appointed.
28 Then shall he return into his land with great riches; and his heart shall be against the holy covenant; and he shall do exploits, and return to his own land.
29 At the time appointed he shall return, and come toward the south; but it shall not be as the former, or as the latter.
30 For the ships of Chittim shall come against him: therefore he shall be grieved, and return, and have indignation against the holy covenant: so shall he do; he shall even return, and have intelligence with them that forsake the holy covenant."
It gets harder with many ideas, but if we are looking at papal power then it makes sense. So the if we check history, "this section refers to the crusades which Papal Rome as king of the north launched to reclaim the Holy Land from the Muslims, “the King of the South,” around AD 1095-1272."
Daniel 11:31-35 King James Version (KJV)
"31 And arms shall stand on his part, and they shall pollute the sanctuary of strength, and shall take away the daily sacrifice, and they shall place the abomination that maketh desolate.
32 And such as do wickedly against the covenant shall he corrupt by flatteries: but the people that do know their God shall be strong, and do exploits.
33 And they that understand among the people shall instruct many: yet they shall fall by the sword, and by flame, by captivity, and by spoil, many days.
34 Now when they shall fall, they shall be holpen with a little help: but many shall cleave to them with flatteries.
35 And some of them of understanding shall fall, to try them, and to purge, and to make them white, even to the time of the end: because it is yet for a time appointed."
Now we come to the corruption of this power. "The abomination that maketh desolate” refers here to the Church of Rome and points to the Reformation period and the persecution of “heretics” by the Roman Catholic Papacy."