In the Book of Mormon, in Omni, Mosiah king of the Nephites flees the land southward and heads for a new home. With him he brings the last stragglers who represent the descendants of Nephi, Sam, Zoram, Jacob and Joseph. These people arrive at a very different location near the river of Sidon. At this river they discover Zarahemla called the descendant of Mulek who had been a son of the last king of Judah.
From there on out these people are viewed as more Jewish people in the New world, they had lost their language, according to the Nephites and their culture. They needed to be saved from there fallen state and in the Nephite language were taught the gospel and converted.
The problem with this story, it is hard to imagine. The last king of Jerusalem, Zedekiah, was a puppet king who got a bit too full of himself and had been crushed by Nebuchadnezzar II. In the biblical story Zedekiah and his followers were captured fleeing Jerusalem and all of his sons were killed and he had his eyes burned out and was taken to live in Babylon until he died.
If one of his sons, Mulek, did escape as it has been contested. He might have done so with other family members, either before the seige at Jerusalem or during the flight, he would have to have gone north to the Phoenicians in Tyre or Sidon. The Phoenicians were closest civilization near Judah who might have given him aid and comfort, as these articles here and here argue.
The Phoenicians appear to escape the problems of Judah and Israel as staging ground for Egyptians and wars for everyone else. They make a reasonable candidate because they have the ship faring know how to take a group of people to a new land. There are ideas that they might have even traded with ancient South America at one time.
Others have argued that this explanation may be weak. That rather than the Mulekites coming from Jerusalem that may have been a Nephite misunderstanding or myth created to develop unity amongst two people who united. Some argue that the Mulekites are Jaredites survivors.
Those outside of the community which believe in the book of Mormon see the new limited geography description as covering for lack of evidence.
However, we know from biblical archaeology that much of what we thought about the size of the Kingdom of Israel and the history of the Jewish people is sometimes mixed with political realities. Which means some biblical text can be seen as redacted or framed by the later writers to fit their views. So too has the book of Mormon been redacted by Mormon and Moroni.
So therefore the story of the Mulekites or even the understanding of Moroni and Mormon of how the various parties grew together is effected by this information. Omni’s description of the origins of the people seems to win the day for all the rest of the Book.
15 Behold, it came to pass that Mosiah discovered that the people of Zarahemla came out from Jerusalem at the time that Zedekiah, king of Judah, was carried away captive into Babylon.
16 And they journeyed in the wilderness, and were brought by the hand of the Lord across the great waters, into the land where Mosiah discovered them; and they had dwelt there from that time forth.
17 And at the time that Mosiah discovered them, they had become exceedingly numerous. Nevertheless, they had had many wars and serious contentions, and had fallen by the sword from time to time; and their language had become corrupted; and they had brought no records with them; and they denied the being of their Creator; and Mosiah, nor the people of Mosiah, could understand them.
So according to Omni they could not understand each other, he says because the Mulekites language was corrupted but if one looks at what Moroni describes of the language of the book it is obvious they are not the only ones.
Accepting Omni’s word at face value. The Mulekites are descendants of Mulek a prince of Judah.
Yet one notes that Omni said they were very numerous. So that they were much larger than the Nephites. For them to immediately accept the Nephites means they very likely had a shift in leadership rather than a wholesale merger. This may be because Zarahemla is without sons or maybe because the Nephites and the technological advancements or reading had given them an advantage.
Unfortunately we do not understand all the political ramifications of the wholesale take over of the people of Zarahemla by the Nephites. So really one must ask if the idea of kinship bonds was forged by the Nephites to alleviate the political situation. Benjamin or possibly even Mosiah is married to some daughter of Zarahemla, instant monarch, just add offspring.
If we are to ever come to grips with the historical as well spiritual aspects of the book of Mormon then I believe we will have to allow people the right to create a legacy which might be different than what was on the ground. I think it is possible that the people of Zarahemla were not Mulekites or Jaredites, though a remnant could have been found in them. In fact one might suspect that these people were Amerindians who lived in the area and were convinced of a new ancient origin, from almost four hundred years previous, through the political unification and cultural integration of the Nephites.
Of course this idea of taking the Book of Mormon as literal history and not just an out of time spiritual record has been discussed, here, here and here and even here (if I can ever find it I will add it later… sorry).