Textual: Mormon begins a series of statements here that suggest that he is abbreviated too heavily for our modern tastes. The first important note to make is that he appears to be shifting in his main source from the account of Aaron back to Ammon’s record. Ammon is listed as the principal in this verse, and we may expect that this information therefore comes from his record.
It also appears that either the source material was deficient, or that Mormon is being less that careful with his sources, as it is difficult to be clear about the movements of peoples through the places and events of the next several verses. Because of the lack of clarity, we shall have to attempt a logical reconstruction based on the material he does supply us.
Historical: We find Ammon and his brethren “and all those who had come up with him…” seeing the preparations for war by the Lamanites. They come to Midian where Ammon meets “all his brethren,” and then they travel to Ishmael, where a council is held that includes Anti-Nephi-Lehi, who is now the over-king, and ruler of the city and land of Nephi. What comes next in the relating of the history is the most important part of the narration, but we need to understand this passage in order to understand the coming event.
First we have Ammon, his brethren, “and all those who had come up with him.” This suggests that Ammon and his brethren are leading a group of people. Since Ammon and his brethren have been preaching in different cities, it would be reasonable to assume that they have gathered the believers out of the various cities, and are bringing them, en masse, to a new location. The hypothesis that these missionaries were bringing the converted people with them would appear to be born out in the verses that begin to speak of the Anti-Nephi-Lehies as a single group. For instance, in the very next verse Mormon tells us that they all refused to take up arms. The speech of the king appears to be directed to the entire body of the converts, and verse 17 suggests that all of the people are gathered together. Thus this supposition would appear to be on firm ground.
When the large group comes to Midian, they meet some other undefined body of people who have similarly gathered at Midian. This might include some of the missionaries, but might only be converted people from some of the cities. This is the only Book of Mormon mention of Midian, so we cannot give any real indication of where it lay.
Part of the geographical problem of Midian is the rest of the events described in this chapter where Mormon is less than clear. We have two important facts. The first is that “they” went from Midian to Ishmael for a council. We also learn in verse 20 that the massacre occurs in the land of Nephi, not the land of Ishmael. This provides the geographical issue that Mormon has confused.
What we must do, according to the text, is have a large body of people meet in Midian, some people, if not all, going to Ishmael, including the king of Nephi, and then we must have everyone show up in Nephi. The logistics of these moves are not described, so what follows is a reasonable reconstruction of what might have happened.
First, we know that many of the cities where conversions took place were to the South and West of Nephi. The locations that were the strongholds of the Amulonites and Amalekites were to the North and West of Nephi, and north of Ishmael. It appears reasonable, then, that Midian was a convenient collection place that lay between the more outlying cities of Shemlon and Shilom and Nephi. When the newly named people of Anti-Nephi-Lehi followed their missionaries out of the cities, they met at Midian from various locations, and at Midian became a single body.
At Midian, the group would have split into two different bodies. The larger body of the Anti-Nephi-Lehies went up to Nephi, where they remained until the invasion by the Lamanites. This would be a logical point of refuge both because it was the location of their king, and as the central city of a larger collective, it may have had the better fortifications or army.
Rather than see the entire group as the “they” that left Midian for Ishmael, I would suggest that “they” consisted of Ammon and his brethren. They went to Ishmael for a war council, and that purpose would be hampered with the larger numbers of people who were emigrating. The reason for the meeting in Ishmael rather than Nephi may have to do with the closer proximity of Ishmael to the strongholds of the Amulonites and Amalekites. Thus the council of war might be held in a location that was closer to the essential knowledge needed of the status of the enemy. At the end of the council of war, all of the believers would have retreated from Ishmael and Middoni to gather at the larger city of Nephi.