Culture: These cities would comprise the territory under the rule of the “king of the Lamanites.” Since the sons of Mosiah had protection to preach in these places, we may assume that they concentrated in these cities. The list includes Middoni and Ishmael, each of which had its own king. Therefore, the rest of the cities almost certainly had their own kings. Thus Lamoni’s father controlled (at least) eight cities, including his own city of Nephi and the city inhabited by Amalekites and Amulonites (v. 14).
It is not possible that all of the residents of all of these cities were converted. First, such an occurrence would simply not be realistic. The phrase beginning most verses, “and also of the people… ,” refers to the conversion of some of the people of each city.
Second, the events described in the next few chapters could not possibly refer to the combined inhabitants of six cities. Though Mormon never tells us that the converted Lamanites migrate to a single location, the story of the Anti-Nephi-Lehies strongly implies it; the population was small enough that a single land (and by implication a single city) sufficed when they joined the Nephites. We should therefore understand that only some of these people were converted and left their native cities to form a new community which Mormon does not describe.