Cultural: 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 went where their protection allowed, and that the successes indicate cities that were under the control of the king of the Lamanites. Notice that we have specifically mentioned Middoni and Ishmael. We already know that each of those cities had their own king. We may readily infer that the rest of the named cities also had their own king. Thus Lamoni’s father controlled not only the city of Nephi at the center, but also seven others (including the city housing the Amalekites and Amulonites in the next verse.
Textual: We must take care in the way these verses are read. It would be simple to suppose that all of the residents of these cities were converted to the gospel. That cannot be the case. First, it is probable that the phrase that leads off most verses, “and also of the people…” refers to the conversion of some of the people of each city. Simple experience tells us that it would be unusual in the extreme for every single resident in these cities to covert.
Secondly, the events that will be described in the next few chapters do not read as through they could possibly refer to the combined inhabitants of six cities. Though Mormon never tells us that the converted Lamanites migrate to a single location, all of the subsequent events imply that single location, and later a population small enough that they might be given a single land, and by implication a single city, when they join the Nephites.
At this point, we should therefore understand that only some of these people were converted, and that they left their native cities to form a new community which Mormon did not describe.